How to Install a Dishwasher

Dishwasher installed

Whether you’re putting in all new appliances or simply replacing a worn-out machine, installing a dishwasher yourself is a DIY project that’s not that difficult and can save you a hefty installation fee.

Preparations for Dishwasher Installation

The first step is making sure the machine will fit in the opening. Most standard dishwashers require a 24” opening. If you’re installing new cabinets, it’s important to consider the width of the dishwasher ahead of time. The height of most machines is adjustable within certain limits, but check to be sure the dishwasher you plan on purchasing will fit your opening before buying.

Depending on your cabinet configuration, you may need to drill one or more holes to run supply lines, electrical wiring, and the drainpipe through. Hole saws make quick work of drilling larger diameter holes.

Remove the faceplate at the base of the machine to access the supply line inlet and electrical box. It’s a good idea to connect the wiring, drain, and supply lines before pushing the dishwasher into the cabinet, since it makes it easier to access the underside of the machine.

Connecting the Drainpipe

Start by connecting the drainpipe to the discharge pump. Many local building codes require dishwashers to be vented using an air gap to prevent the siphoning of water from the sink drain or disposal. Mount the air gap in one of the sink holes or drill a hole for it in the countertop. Connect the drainpipes to the air gap and secure them with hose or spring clamps.

If an air gap is not required, loop the drain hose up near the top of the base cabinet, and attach it to the wall with a strap to prevent backflow from the sink.

Run the drainpipe to the inlet of the garbage disposal and secure it with a clamp. Many garbage disposals have a plug in the inlet, so be sure to remove it first.

If there isn’t a garbage disposal or an existing drain for the dishwasher, replace the drainpipe under the sink with a dishwasher branch tailpiece and install it above the trap under the sink.

Connecting the Supply Lines

Most dishwasher supply lines are 3/8” diameter, but check to make sure you’ve got the right parts before starting the job. Begin by turning off the water and installing a dual outlet shut-off valve to connect the dishwasher supply line to the hot water pipe under the sink. One outlet on the valve provides hot water for the sink faucet while the other attaches to the dishwasher supply line. This will allow you to turn the water off to the dishwasher separately from the faucet.

Connect one end of the supply line to the shut-off valve and the other end to the water inlet on the underside of the dishwasher using a right angle elbow.

Where needed, apply Teflon tape to the male threads to prevent leaks. Supply lines should be hand tightened then given a solid quarter turn with a wrench.

Connecting the Electrical Supply

Always be sure to cut off the power to the dishwasher by flipping the circuit breaker before attempting to connect the electrical supply. Run the cable through the back of the electrical box on the dishwasher, and connect the hot (usually black) and neutral (white) wires to the corresponding wires in the box using wire nuts. Be sure to connect the ground wire to the green screw and replace the cover on the box.

Turn the water back on and check for leaks, then turn on the power and run the dishwasher through a full cycle. If everything works properly, slide the machine into the cabinet, being careful not to crimp or pinch the pipes. Plumb and level it by raising and lowering the adjustable feet on either side.

Screw the dishwasher to the underside of the countertop to hold it in place. When attaching the mounting screws to the plywood used to support a stone countertop, be sure the screws do not protrude into the stone.

Attach the faceplate to the base, and your new dishwasher is ready to go!

Helpful Tips

  • Examine the dishwasher before bringing it home. Look for scratches or dents and make sure the necessary hardware is included.
  • Check the size of all supply lines and connecters before installing a new machine.
  • Make sure to close all shut-off valves and turn off the circuit breaker before disconnecting an old dishwasher.
  • When disconnecting an existing machine, be prepared with towels and a shallow pan to drain any excess water remaining in the lines.

Further Information

Find Peace of Mind As a Homeowner with a Home Warranty


  1. This is the most helpful article. I am putting in a dishwasher tonight and I’ve got this bookmarked. Thank you for your website and thank you Mr. Libby for a great article.

  2. The maximum distance the dishwasher can be from the sink drain will vary depending on the make and model, but should be spelled out in your manual. Usually they range from 5′ to 10′.

  3. I’m trying to take out my dishwasher from the sink to see where is the smell of cigratte is coming from because I have neighbor that smokes and I could smell it through the sink where my dishwasher is place so if there is any tips on where or what I could do to prevent this smell please help.


  4. I am trying to replace my dishwasher. When I took the old one out I notice the electrical wire was plugged into an oulet that just laying on the floor, under the dishwasher. The drain hose was also laying on the floor. Is this common practice? Can the elecrical outlet be placed behind the diswasher? Or does it have to go in the cabinet next to the dishwasher openning. What about the drain?

  5. I’m installing a new dishwasher and someone told me that you must have the drain up high above the sink trap, is this correct. Someone else said that it’s allright to just let it drain by gravity into an existing drain line running along the joists in the basement. I would appreciate your info on this.. thanks , ED

  6. After my dishwasher was installed, I noticed that the faceplate was protruding beyond the cabinet. Is this correct? Should the dishwasher be pushed in to the cabinet further and then reintall the faceplate?

  7. Hi Ed,
    Since dishwashers use a pump to drain, gravity is not needed. As noted in the article above, the drain hose should either have an air gap mounted on the kitchen counter or loop up near the top of the base cabinet to prevent backflow from the kitchen sink. Also, be sure to attach the dishwasher drain line above the sink trap to keep sewer gases from coming through the drain line.

  8. Here’s an odd thing: I had a new dishwasher professionally installed a few months ago and we had a drain problem almost immediatly (cleared with Drano) and now I’m finding what looks like white particles in all the faucet screens everywhere in the house. They look and smell like dishwasher soap. Any idea what is happening here?

  9. Doug,
    June 20th, 2008 at 12:14 am

    Perhaps you turned the water temperature up on your water heater. I think these white pieces are coming from the water heater. I have seen some white plastic pieces in the aerators which ended up being the cold water dip tube inside the water heater. It was breaking up. Dishwasher soap cannot get into the water supply. Hope this is useful. Karl

  10. Doug,
    If you are finding “white particles” in the aerators of your faucets you should probably first consider calling a Licensed Professional Plumbing Contractor whom KNOWS how to propery service this device / knows what I suggest herein and after you tell him the symptoms he need be able to recite what I speak of here before you allow him in for repairs! The Contractor should be skilled in looking at the “DOWN TUBE” on the cold water inlet to the water heater which is a good 4′ or so long. Doug there were hundreds of thousands of DEFECTIVE down tubes installed in MANY water heaters some time ago. The defective down tubes basically disintegrate into tiny white particles and must be replaced, a tell tale sign this is, but not the ONLY diagnosis as well, certainly the most plausable.
    If your water heater is older than 5 years old I would suggest just replacing it Vs. fixing it Doug if the down tube is found defective. Water heaters simply do not last as long as they used to and if your get 5 years out of a water heater anymore your doing GOOD. BELIEVE IT.
    The down tube in question delivers cold water to the bottom of the water heater and w/o it your water heater will not function correctly Doug and this condition could COST YOU MONEY and heartache. Remember hot water rises so it only makes sense to deliver the cold water coming into the tank to the bottom, yes? YES! Check it, the down tube out, and fix as necessary and SAVE FUEL COSTS Doug.
    DO not expect to be able to re-use the flexible water connector (2) you may see up there, get anew BEFORE you touch them Doug. The’re only designed to be used one time and reuse is asking for trouble. Your licensed professional plumbing contractor will NEVER re-use items such as these.

    Regards and Good Luck Sir;
    Master Plumbing Contractor

  11. I just had a new Dishwasher delivered. The old supply line would not connect to the new 3/8 inch elbow joint under the dishwasher. I bought a new braided 3/8 inch supply line that connects to the elbow piece but it would not connect to the water supply valve. I even tried a 1/2 inch connector but that was too large. Any suggestions?

  12. A professional installed my new dishwasher however they did not install the screws into the granite countertop brackets. Now the diswasher moves about and I have to push it back into position after every wash cycle. Is there a trick to installing the screws into a granite counter top?

  13. Hi! I am going to be installing a dishwasher and needed to get an answer to a question before I start. One of the reasons I stopped using the dishwasher I have now is because the small spout near the faucet on the kitchen sink would spray lots of water every time I used my dishwasher. What causes this can I fix this myself so that I could install my new dishwasher? Please Help!! Thanks!!

  14. How far into the cabinets should the dish wash be set. We redid our kitchen completely & added a built in dishwasher, the sides of the dishwasher are set to the cabinet’s depth. This makes the door stick out past the rest of the cabinet doors/drawers. I have seen some with the dishwasher set back further so the door when closed lines up with the rest of the cabinets. Is there a right or wrong way the dishwasher should be lined up?
    cabinets. Is there a right or wrong way the dishwasher should be lined up?

  15. This is the best website for do it yourselfers like me and I am one heck of a carpenter for a gal anyways the descriptions and the visual are both wonderfully put together for the maximum easy to understand and do it yourself I love this website Its the best

  16. Can a dishwasher be installed underneath a cooktop that was installed in the countertop? Are there requirements for minimum space around the unit? Thanks.

  17. I’m installing a dishwasher. I’ve installed the hot water riser and have connected a T to it with a valve coming off the T for the dishwasher supply. The electrician installed an outlet box in the botton left corner of the sink cabinet. The valve sits at a height that puts it in the middle of the outlet box and is about 4 inches from the box. My question is, is that arrangement ok? Would it pass inspection? THanks,

  18. I’m most likely going to have a dishwasher installed by a professional, since I’m not the most handy guy in the world. I have one question….I don’t have any hook ups available now. Who do i get to do this? Do I need to hire an electrician to get electric to my spot, or will with plumber I hire be able to do that as well?

  19. Our brand new duishwasher did a far worse job than our 40-year old Kitchenaid. The service person came out and immediately identified what he thought was the problem: He said that since the installation was in an island that had the drain trap below the floor and below the level of the sink drain, what was happening was that the water in the DW was being siphoned out of the DW. Hence we weren’t using enough water to wash and rinse, and it affected the drying cycle too. Does this make sense, and what is the solution? Thanks.

  20. we installed a new dishwasher and it doesn’t rinse the dishes good . I have to rinse almost all the dishes again and wash a lot of the top rack, which are glasses, over. Do you know what the problem maybe.

  21. I am installing a dishwasher myself and all was well until I realized that the standard 8″ branch tailpiece was too short. Do they come longer, or am I going to have to call in a plumber?

  22. You may be loading the bottom of the washer too full or with large pans that do not let the water spray reach the top level of the washer,

  23. Al, if you make a loop in your drain hose near the top of the cabinet opening, you won’t need the p-trap and you should clear up the problem

  24. hilda, I would think you would have to change the supply hose to fit a pre-plumbed line, change the drain hose to make a seal and maybe put feet on it instead of wheels so it doesn’t vibrate or roll any more? hard to say since I don’t know what you have or what you had

  25. Rob, if you hire an “installer” he/she will probably be able to do the whole thing, if you hire a plumber, you will probably also need to hire an electrician.

  26. Jennifer, you can find almost anything if you look in the right place. I would go to Home depot or one of the other stores and explain the problem, even if there is not one “factory made” chances are you can put one together that will work fine.

  27. I have a new dishwasher to install, but first I have to take out the old one. I have no idea where to start. Is there a website or page that gives directions on how to take out a dishwasher?

  28. Dana,
    Dishwashers slide in and out on rollers and are usually held in place by two screws at the top of the cabinet or countertop (see last picture in article above). Connections for water and power can be accessed by removing the cover plate at the bottom of the dishwasher. Start by turning off the power and water to the dishwasher, then remove the screws holding the dishwasher and take off the cover plate. Detach the electrical wire, water supply, and drain pipe from the access opening then slide it out.

  29. I am installing a new Dishwasher and need to know what to do with the drainage hose. This is an old home. The dishwasher was installed on the main floor with the drain hose running through the floor into it’s own drain pipe in the basement. The connection is above the Ptrap. There isn’t an airgap and there is no garbage disposal. Can I hook up the new DW drainage to the existing drain pipe below the floor? Do I need an airgap or can I loop the Drainage hose at the top of the cabinet before running through floor and connecting to drain?

  30. I was wondering how far I can run the drain line and not interfere witn the operation of the dishwasher? What I am considering would all be done on the same floor level. I have a new Whirlpool machine if that mekes a differance.

  31. Im also looking to install a dishwasher in a kitchen that has never had one. I have a perfect spot next to the sink however, There is no electrical hook up. There are 2 outlets left and right of the sink. The opposite outlet is used by the frigde. Is it common to tap into an outlet or do I need to run a individual power wire to the breaker for the washer only?

  32. Did anyone answer Stan’s question regarding installing the drain hose through the floor into the basement? I am considering doing the same as my sink is located on another wall from the dishwasher.

  33. I am installing a new dishwasher and my house has never had one. Do I need to hire a plumber and electrician to install or is this service usually covered when you pay to have it installed when you buy it from the store?

  34. My daughter wants me to in stall a new dishwasher for her we are not replacing one. It will be on the other side of the room from the kitchen sink. So could I install one to where it would have its own drain line. To where it would be connected under the kitchen floor and not brought up above the sink trap?

  35. Hi, I am renting my house out that was built in the 50’s and would like to add a dishwasher. It looks like it has a hookup for a dishwasher (hot and cold water lines) but they are not under the sink. There is also a drain hole in the floor where those lines are. Based on the article above, I’m not sure that’s right. Any suggestions? Thanks!


  37. You can connect the drain hose to plumbing below the floor. The same method of the drain hose going up to the top of the dishwasher opening is still required to prevent the siphoning of water from the dishwasher as well as backwash and sewer gas entering from pipes below the floor. from entering dishwasher. Do not connect to 4 inch drain lines from sources such as toilets for health reasons. This was the only way it could be installed in my home as the sink was in the island 20 feet away from the dish washer. Hot water line connection is a must cold water will not work with detergent at all, no exceptions! Dishwashers should be installed on its own circuit breaker and not shared with a kitchen outlet do to the risk that if the outlet is used at the same time as dishwasher it will overload that circuit. Hope this helps.

  38. This is a great site. Hope you can give me advice. We are having a new countertop which is exactly the same size as our existing one installed over our dishwasher that has been in the same place for a long time. Do we need to take out the dishwasher to install the new countertop? Our kitchen cabinets are remaining the same and in the same place. The sink is directly left of the dishwasher.

  39. Larry asked a question on 15 Oct about water water remaining inj the diswasher. Does anyone know what the cause was?
    I have the same problem and loke hom am about to replace the machine. I bought the house a few weeks ago and think I inherited the problem. Still runs just ends up with a pond in the bottom.

  40. we have a sears elite dbl door dishwasher, can not be install into the sink…we need to go through the floor .. What is needed to make this possible and work correctly..Thank You

  41. to install the new dishwasher, what water supply need to connect is it hot water or both cold & hot water. please answer my question thanks

  42. I had a new Bosch dishwasher installed. After it washes the dishes a smell remains in the dishwasher. Using vinegar does not remove the smell. Did the service person install the dishwasher correctly? The old washer did not have the problem. The discharge is connected to the disposal.

  43. “Supply lines should be hand tightened then given a solid quarter turn with a wrench.”

    I’ve been looking all over for that specific information. I don’t want to overtighten or undertighten.


  44. We recently installed a new dishwasher in our 43 year old home and all went well. The problem is there is an uneven gap between the dishwasher and the end of the cabinet. I purchased a piece of matching wood to fill the gap and would appreciate some advice on how to trim the board to fit as well as how to attach it.

    Thank you in advance for any suggestions.

  45. Linda,
    Your best bet, if I can picture what you are describing, is to use a table saw with a fine finish blade on it to “rip” your piece of wood to the proper width. If you don’t have a table saw or access to one, you may be able to get Home Depot or one of the other stores to do it for you.
    Then, depending on the width of the piece you are going to use, you will need to attach it to the existing cabinetry, as you describe. If it is less than a half inch or so, I would recommend glue and a couple of small trim nails. If it is wider than that, you will likely want to glue and screw. You will need to countersink the screws so they dont protrude and interfere with the dishwasher when you slide it back in.


  47. We are having a professional (?) installation of a replacement built-in dishwasher. They arrived and said I need to get a non-standard 12 foot flex steel supply hose and a 1/2 to 3/8″ adapter for the water shut-off valve, as well as a 10 or 12′ plastic drain hose. They will not install on the existing copper hose, and I respect that — seems like it will cause leakage if they try. My question is-WHERE do I find the 12 foot supply hose? I’ve called all the big box stores, which were suggestions from the installer. I’m at a loss, and wondering if I should try to move the location of the dishwasher (which is 2 cupboards away from the sink/water shutoff valve. I’m on a limited budget, so think that would definitely be more expensive!


  49. judith – if you in fact removed all manuals/warranty cards/etc from inside unit before cycling, then lets talk drainage and hoses, etc (have to bring up manuals thing since I saw someone do it before – no insults intended whatsoever – easy fix too if it was) Next, after making sure your drain hose is properly attached to unit, does it go to garbage disposal inlet (if so, be aware of plug inside inlet to garbage disposal – disconnect drain hose at garbage disposal and poke screwdriver into garbage disposal inlet – there should be no obstructions – if there is, its probably the “plug” and you can punch it out with screwdriver – punch out thoroughly if you have to do this)Aside from that, if your dishwasher just isn’t draining, your looking at a blocked or kinked drain hose, a faulty pump, or some other obstruction. If this is brand new, be sure that you are in fact getting water to the unit (sometimes have to run for a minute or so to bleed air out of line) If you still have trouble, give more info about how its hooked up (drain hoses, air gap or not, garbage disposal or not, etc) and any other observations. Can help better with more info. Aloha

  50. To Cheryl:

    GE makes under the sink dishwashers. You might have to replace the sink, too, with a reduced depth model. But, it could be a good choice for a very small kitchen…

    The website link is to GE’s site of under the sink dishwashers.

  51. My Husband and I are installing a dishwasher into our kitchen. There was never one there.We have the prefect place for it.I have all the pices that I need for the washer but I can’t figure out how to install it. fi anyone can help me I would very much appericate it.

  52. Where should the electrical outlet and the hot water supply line be located on wall at the back of the dishwasher cabinet–left, right, and how many inches above the floor? . We are putting the DW in across from the sink in a U-shaped area. We do not want to interfer with the DW tub or components. Also, to avoid an overly long discharge hose, could a P-trap be installed in the back wall of the DW area and head toward the main stack in the basement?

  53. Can I use the outlet that my gas range uses as an electical supply for the DW? I have also heard of some poeple creating a “plug” for the DW. Is this feasable?

  54. I’ve installed the dishwasher in our new kitchen, and we have no holes in the granite counter top, as our contractor said it was better to mount through the sides to prevent the granite from cracking due to the vibration of the machine. This made some sense but I can’t figure out where to drive the mounting screws. Think you can help.

  55. I am replacing a 10-year old Whirlpool dishwasher with a new Bosch dishwasher…. And a pretty handy friend who has installed a dishwasher before has offered to install it for me. The store where i bought it from said that a new water line will come in the box but that many people use rest of connections that their existing dishwasher is useing. Does that sound right? Or should old connections/hose be replaced?

  56. We had our countertops replaced, which required that the dishwasher be removed and unplugged. My husband reinstalled the dishwasher, but now the door won’t close properly. Any suggestions?

  57. Lorrie,
    If the adjustable feet on the dishwasher are set as low as they will go, you may have to remove the countertops, put shims on top of the base cabinets, then reattached the countertops.

  58. We had drain problem also. Our sink drain where you hook dishwasher drain hose to was plugged,just stuck a screwdriver in hole and it cleared easy. Try putting drain hose in sink if dishwasher drains you have same problem.

  59. I just bought an LG Washer/Dryer combo apartment size unit, under-the-counter dishwasher width. This is a one unit machine, washer and dryer at the same time, non-vented (has two drums) that fits where the dishwasher is. It is a 120w unit. Two questions: 1) I had laminate floor put in a few years back and I believe it edged-in the dishwasher. How – if at all – could I remove it without disturbing the floor? 2) I am assuming the existing hookups – electric and plumbing – are adequate. Should I worry? Are the dishwashers usually 110w or 220w? I never used the dishwasher, but the previous owner and subsequent tenant both used it extensively. I moved in 10 years ago and promptly “converted” the DW into a storage cupboard – a more appropriate function, I have no use for DW for one person.

    Thanks for any pointers. Delivery set for Saturday Feb 28, 2009

  60. We had a new dishwasher installed in our remodeled kitchen. There is a gap under the counter and you can see the mounting brackets. The installer is no longer available. In looking at dishwasher displays, there are no gaps between the top of the dishwasher and the counter. What can we do to “fix this”? Anything you can suggest will be helpful. THANKS!

  61. i did conect my dishwahser and its turn on but the water wont came inside, it can be the problem if i put a cold water suply? do i have to change to a hot water suply to fix the problem?

    • Raul,
      The problem shouldn’t be with using a cold water supply line. The only reason I know of to use a hot water supply line is to preheat the water for the dishwasher.

  62. i am fed up w/the kitchen without a dishwaser until we can afford to remodel. can i buy a dishwaher, install it, then move it and re-install or will i have trouble with the connections/seals. thank you

  63. My DW drain hose goes through the floor to a sink trap in the basement. The installation directions say the drain should be 20″ above the floor. What is the reason for this? Is there a simple solution that allows for the drain to remain in the basement? Should I loop the drain hose up 20″ before it goes through the floor? Thanks for the help.

  64. We are installing a dishwasher 5 foot across from the sink/disposal no access to the sink…. how can we make this work with the air gap? We have the plumbing in place already but not sure what to do to make sure the d/w drains properly.

  65. HELP!
    I’m replacing my counter tops with granite and replaceing all the appliances but I’ve encountered a problem with the height of the dishwasher opening being to short. It’s 33-1/2″ from the Pergo floor to counter top but it appears the face plate of the dishwaser is the only thing sitting on the Pergo. Just behind that is the orginal floor which gives me another 1/2″. I’ve been told that if I cut an opening in the pergo floor out 2″ beyond the position of the dishwasher that would make it possible to move the dishwaser in and out from the counter. I dont want to find out after the fact this wont work. Any suggestions?

  66. Hello , I’m thinking of doing a lit shuffling around in my kitchen and putting a built in D/W where the fridge is my question is it’ll be about 6 feet from the sink area ,I think this is OK for the supply water line but what about the drain hose , if the drain hose is not long enough can you get couplings to join more length on or are you only permitted to have a certain distance?

  67. The front panel came off and we have no idea where to start in putting it back on. Do we need to check the springs, latches, etc and what holds the front panel onto the door?

  68. We are installing a new dishwasher where there has never been one. We’ve tried to level it but when we check with a level in one spot it will be level, move it a couple inches and the bubble will be partly outside one line lines (max 1/4 of the bubble– How much of a problem is this? How level does it have to be?

    • Hi Rich,
      I’m not sure whether you’re using the level to check the floor or dishwasher itself, but your best bet is to use a 2′ long level to measure the entire width of the dishwasher by resting it on a flat section of the dishwasher frame.

  69. In replacing my faucets due to leakage, As a preventive measure my newphew rerouted the air gap to the counter. Now water is coming out of it. I dont want the air gap on the counter (as it wasnt there before). What can be done?

  70. I just installed a new dishwasher and ran it through the cycles and now I’m hearing vibration coming from underneath when the water is draining. Any ideas? I put a level on the DW and it shows to be level everywhere.

  71. I cannot get the nut off of the hot water line at the bottom front of the dishwasher. How can I complete removing the old dishwasher without removing that nut? Can I just remove it from under the sink and replace it with flexible stainless steel water line?

  72. I have two questions, the first, if only one can be answered, is the most frustrating one!

    My husband installed our new dishwasher, but whenever I wash dishes in the sink with the garbage disposal, I get bubbles up the drain on the other side, in the sink with the hand-washed dishes. Is there a way to fix that?

    Also, when I load the dishwasher, top and bottom doors pulled out, the dishwasher ’tilts’ forward, as he said there was nothing on top to connect it to, since we removed the old countertop and now it is silestone top. Is there way to secure that in place so it does not tilt forward?

  73. I replaced a the dishwasher next to the sink. It makes a grinding noise during some cycles and can be stopped by turning on the faucet of the sink. The drain is connected to the disposal. Everything else works fine and it cleans the dishes very well. When i get the grinding noise it also vibrates the pipes. My guess is an air lock that I didn’t have a problem with before. how do I get rid of it?

  74. I just removed my disposal and now the dishwasher ocasionally fills up with disgustingly nasty smelly water.
    Should there be an upward loop in the drain hose to keep water from draining from the sink back to the dishwasher?

    • Hi Gary,
      Yes. If you don’t have an air gap installed next to your sink, you need to have the drain hose loop up and attached beneath the countertop to act as a trap and prevent your sink waste water from going into the dishwasher. See the section on “Connecting the Drainpipe” in the article above.

  75. I have a problem with the airgap on my Kitchen-aid dishwasher. It appears to be installed correctly, but everytime the washer runs, there is alot of water comming from the airgap and onto the counter. I haven’t found a decent article discribing exactly how it is supposed to work but I would think that it should almost never release water, unless there is a back-up. Can you tell me how it is supposed to work? Is there a troubleshooting guide? My owners manual isn’t any help. Thanks

  76. I used to have a washer and dryer in my kitchen, which have been relocated to the basement. I am installing a dishwasher where the W&D had been. I have an existing drain line and hot water supply that the washer was connect to, but I am wondering if I can use the electrical outlet that is in place. I know dishwashers are usually hard-wired but is there anyway I can install a plug and use the outlet? Thanks for reading.

  77. I don’t understand what an “air gap” is, or how I can tell if my old dishwasher that I am getting ready to replace even has one. How can I tell?? I have looked at your article, but I still do not know. PLEASE HELP!

    • Hi Hanna,
      An air gap acts as a vent for the dishwasher discharge pipe to prevent waste water from the sink from backflowing into the dishwasher. It’s usually installed on the back of the countertop near the dishwasher or in one of the holes on the back of the sink. If you don’t see it protruding from your countertop or sink, you probably don’t have one.

  78. This is the most helpful article. I am putting in a dishwasher tonight and I’ve got this bookmarked. Thank you for your website and thank you Mr. Libby for a great article
    You realy explained it so a kid could do it Thanks again.

  79. I’m putting a dishwasher in an island five to six feet from the sink. If I loop the DW drain line up under the counter then down through the floor and back up to the sink’s disposer, it will be over the 10′ max for the drain line.

    Can I do the loop under the counter and then just “T” directly into the waste line coming from the sink (under the floor)? The T would be downstream from the sink. Would I need an air vent?

  80. Thanks for all of the help, Ben.
    I recently installed a new sink, and put a new air gap in. Approx a week after installation, the inside of the dishwasher smells moldy and there is a strong moldy smell from the airgap, as well. I am confident I hooked it all up correctly and water seems to be draining alright (if I remove the insert in the airgap, water shoots up when the dishwasher is evacuating), so I cannot figure out what problem I’m having here. Do you have any idea what could be causing (what seems to be mold in the drain line of the dishwasher)?

    • Hi Jason,
      Be sure the drain line for the dishwasher is upstream (above) the trap for the sink to keep sewer gases out. If the dishwasher drain line has been there a while, you might want to take it off and run some bleach through it to kill any mold, or replace it with a new one. I had problems with the glasses in my dishwasher smelling moldy, and solved it by running it on the hi-temperture wash cycle where the water is heated to kill any germs. You might try that as well.

  81. I have a relatively new (3+ year) ‘premium’ dishwasher that is now draining during the wash/rinse cycles as the unit runs, leaving the dishes less than clean and the unit running without any water during some of the longer cycles. Is there a valve or such that I can find and see if it’s stuck open, or???

    Thanks much for your kind help.

  82. Our dishwasher was not installed properly and continues to “fall out”. The granite is above, so the securing is put on the sides. Nothing is holding the machine past a few months or weeks, now days. what is suggested for securing it in? There is no plywood under the granite/stone. Thank you.

  83. Danny, I have a dishwasher that won’t drain the water. It leaks from the front but the water won’t drain out at all. I checked the hose that it suppose to drain into my Garbage disposal, but that’s not the problem. Any other ideas I can check on? They charge $90.00 just to look at it and $90.00 an hour plus parts! Any suggestions would help and save me money during these times.

  84. Hi There,
    I’m looking to buy and install an 18″ dishwasher for my condo that has never had a dishwasher. I’ve got a small sink with hot & cold water and an electrical outlet where I want to install the dishwasher, and directly behind the spot for the dishwasher is the bathroom. I want to make sure that I have everything I need to put in a dishwasher. Is that it? I’m worried about the draining and the air gaps. I’ve been told that the dishwasher should be on it’s own circuit- how mandatory is that? I pretty much have no idea what I’m doing- so any help would be appreciated!


  85. I just install whirlpool dishwasher.(replace the old one). When I start the dishwasher water come out on the bottom of the dishwasher. what is the problem, all connection are fine, no any leak.


  86. I just had a dishwasher (new) put in by the maintenance company here at the apt I rent from, but everytime we wash the dishes there is alway’s a film and sometimes little food particles on the top dishes only, what could be happening here?

  87. Air Gap is the required height your fauchet must be above your bath tube, just in case the sewer backs up at the same time your water company has no pressure. That distance is in inches 2D” and prevents dirty water being siphoned to where drinking water, called pot, or potable water is supposed to be. Got it ? Who cares ? We all have it ’cause the Plumbers Code saved our lives by preventing disease. Now the funny part ! As the three of us removed the silver cap, about 2D” sticking above the sink ? ? Gotta Go ! Continued when I get back ! Tex

  88. The Air Gap had a plastic cap with “ears”, rather than a screw, like the earlier types. Use a pair of gas pliers to slightly compress the “ears”, wiggle the plastic cap and set aside. “Now what?”, the three of us said. The Dish-washer answered with a column of water about 12 inches high erupting out of the Air Gap. The “Fun of the Fix” came when we saw in the sink, almost disappearing into the Disposal Drain, a slug of “Debris” that prevented a full emptying of the dish washer. Stay tuned for another continuation. Tex

  89. The plastic cap, when first inserted did not seat well. Rotating it 180 Degrees allowed the “ears” to snap into place. This prevents water being pumped out onto the kitchen area, like one of your readers reported. Next time the water does not completely drain, I will use the silver cup to contain the column of water, as well as control where the slug of “Debris” happens to land. Thanks, Danny. Love your Web Page. I am printing it ! Tex


  91. Hi Danny,

    We will be installing a dishwasher in an island with no sink. Is it possible to install a dishwasher all by itself? We would put a shut off for the hot water underneath. Thank you so much.

  92. i installed a new dishwasher. i have ran a few cycles, it has drained propery during each cycle. but after a few days i notice that there is water in the bottom of the dishwasher. i have the drain hooked up thru. my garbage disposal, the previous washer i had never had this problem. the only other thing that i have changed is i changed the sink to a double, and the two drains come to a “t” splitter, before draining strait down.

  93. I am installing a dishwasher in an area that is supposed to be ready for it. The correct connections are present on the plumbing under the kitchen sink and I have a breaker in the panel labeled “Dishwasher”.

    I expected to find power wires after I removed the cabinet, but nothing is there. I cut a small hole in the wall directly under the outlet above the counter to see if there was a wire running down the inside of the wall and found nothing.

    Is there some magical mark on the wall or floor to tell me where the power lines should be or did my builder ( 20 yrs ago ) forget to run the power?

  94. My husband is going to attempt to install a dishwaher in my trailer (mobile home) any advice for him or any suggestions! Any help will be appreciated!

  95. I replaced an original dishwasher in my 1970’s duplex, because it wasn’t getting any water into it. I assumed it was some internal problem.
    I hooked up a new one, and had the same problem. So I disconnected the suplly line from the hot water line , then turned the valve (used for the dishwasher) on, and no water!!!!! The ball cock is open, but no water! HELP

  96. I’m wondering if I will run into problems: I heat my home with hot water circulation, and have a pipe that runs along the wall behind the cabinets (in fact, it runs along the perimeter of the whole house). Our stove already sticks out about 4 inches from the cabinets due to this. Is there enough room at the back of the dishwasher so that this pipe won’t interfere? It sticks out from the wall about 3 inches, and is about 4 inches from the floor.

    Hope this makes sense. Can anyone help?

  97. Our kitchen sink clogged, and as a result the dirty water in the dishwasher did not pump out. After the sink was rooted out, the dirty water pumped out but now clean water won’t pump in. This has happened before and someone told me to turn the hot water feed off and then on again and this would … do something. Anyway, that’s what I did, and the dishwasher started working properly again. This time I’ve turned the feed on and off to no effect. But maybe I’m not remembering what I did correctly. Any suggestions????

  98. So I see that a lot of people have asked this question and none of them have been answered so I’m going to ask it again. How in the world can I install a dishwasher into a home that has never had one? We don’t have a hookup for a dishwasher at all and are “creating” a space for it beside our sink. What is the best way to go about installing it?


    • Hi Casey,
      You would need to tie into the hot water line and drain from your sink and run the appropriate sized grounded wire to the space the dishwasher will be installed.

  99. Air Gap exit next to kitchen sink faucet prevents use of drain plunger on sink clogs unless second person attemots to seal air gap with dish rag while holding down drain plug with other hand and other person operates plunger. Can I put a ball valve in the air gap hose to shut it off while unclogging sink drains ?

  100. I am looking at installing a dishwasher in my mobile home, which has never had one, and was wandering if I can use an exsisting outlet on my range for the power. I know this question has been asked but please give me some instruction on how to install w/o getting into costly ventures. Thanks

  101. I am having new countertops installed and would like to eliminate the aerator for the dishwasher from the top of the counter. What can I do instead?

  102. Hi Danny,
    I hooked up a portalbe dishwasher water line directly to the hot water tank. It is hooked up to the bottom of the hot water tanks release nozzel. It seemed to work fine and the dishes were clean,then about the 3rd time, Ive noticed no water was coming into the dishwasher. I checked for kinks and seems not to be any sentiments clogging. Any ideas? Or should this not be hooked up directly to the water heater. The kitchen is very small, so I came up with this solution.
    Thank Jamie

  103. I’m wanting to install a dishwasher in my kitchen. Never had one here before. the place i want to put is currently a bottom cabinet and a drawer. Can that be cut out and made for a space for the dishwasher? and,,, Is that enough for at least an 18 Inch dishwasher? I did a rough measurement and its like 21w by 27 ht.

  104. Hello,

    I have cut out a 24″ cabinet. Under the cabinet was not tile as their is in the rest of the kitchen. I placed 3/4 plywood down to make sub floor level with the tile. I have all electrical and plumbing complete but the dishwasher is having fitting issues.

    I have a Kenmore with top mounted controls. Are these controls to be visible with the door closed or must they protrude out from the counter top and be visible with the door shut?

    I do not seem to have any room to screw in the top metal secure latches. My counter top is laminate and it has a lip that lowers. Right now the controls on the top of the door are visible when shut. Does this need to be pushed further in? When I do push it in the door gets caught on the counter top. How much of a gap should I have from the counter top to the inside top of this dish washer?

    I thank you for any advise you are able to provide.

  105. Joe: the 3/4″ subfloor may be the problem. If you have the installation instructions for the dishwasher they should explain where the top-mount controls should appear (probably not visible with the door closed). Like Danny explains above, dishwashers come with adjustable feet that allow raising it to be flush under the counter. Be sure that yours are turned all the way in so the dishwasher is as low as possible. If they are and you can’t push it in and the feet are on the tile, then unless you temporarily remove some tile or raise the countertop, it won’t fit.

    If the feet are on the subfloor but it’s not in far enough, then if you remove the subfloor you should be able to get the DW into that lower section, then raise the adjustable feet to be flush with the bottom of the counter. Then if it’s laminate on particle board you screw the brackets on the top of the dishwasher into the bottom of the board. If it’s a completely stone countertop then check your installation manual to see if the DW can be secured on the sides or what other advice they give.

  106. We are replacing laminate counters with granite counters. We are replacing our old dishwasher with a new dishwasher. The salesman at the granite counter company said we needed to get a side mounted dishwasher and to have it installed prior to installation of the granite countertop. The dishwasher installer advised us to remove the old dishwasher and install the dishwasher after the the granite installation. These are two different companies. Who is right in this? Should we install the granite countertops first or the side mounted dishwasher? Please answer soon.

  107. We are having issue with installation of new Bosch side mounted diswasher. Problem stems with “professional installers”…They can remove existing DW (currently have laminate tops–will be replaced with Corian) Pro-Installers state we are to have new counter tops replaced and then they will install new DW (side mount) but have the “counter top 1/2″ higher then existing” How? Does this make sense? We are NOT replacing the floor tiles or the base cabinets. Current DW was in place when floor was tiled and is subsequently “grouted” to the floor! Our choice is to do as instructed above (shim counter top & cabinets) or to “replace” floor!!! PLEASE ADVISE!!!

  108. We are installing a new tall-tub dishwasher. The printed instructions say there must be clearance between the motor and the floor, but do not specify how much clearance. We have 1/8″ clearance when following instructions for a 34-1/4″ counter height. Is this adequate or does this create a safety hazard?

  109. When we had a new dishwasher installed to replace an older model, the installer ran the drain hoses through the cabinet next to the dishwasher instead of through the empty space under the cabinet. He claimed that it was because all the new dishwashers are required to use less water and that to make this work the water supply and drain lines need to be above floor level. Is this true or did we get taken (again)? I lost cupboard space and am not happy about this. By the way, we live in the midwest and there is a basement below this area with open access to the basement ceiling/kitchen floor.

  110. Vicki E. I’m trying to repair a leak near the dishwasher at my son’s house. The water supply and drain hoses run through empty space under the cabinet. I wish I could see the hose so I can figure out if the leak is coming from a loose coupling, a split hose, or something else.
    The hoses can run anywhere as long as the water pressure is enough to let hot water in, and the dish washer’s pump can push the used water out to the drain, without back-flow of sewage or sewer gas.
    The Installer just didn’t want to get into carpentry work.

  111. Can you use a pigtail so you can plug into the wall outlet instead of hard wiring with 12-2 romex into the outlet box?

  112. hi,
    i try to replace a dishwasher.
    i do see under the sink, there is another pipe connects the air gap to the disposal. i connect the drain pipe to the air gap under the sink, but when i turn on the dishwasher, the drain water comes out from the gap to the sink instead of draining to the disposal.
    can you explain why ?

  113. This was very helpful information,well laid out with pictures showing everything.I know now this is going to be a easy install.thanks!

    James K

  114. The water line hookup on the dishwasher end now consists of a blue plastic threaded nipple onto which attached is a hose fitting from the supply. I do not feel comfortable with this plastic/brass connection. Are all dishwashers going this direction – using plastic rather than brass??

  115. Most water inlet valves are plastic and yes they fit up with the brass hose fitting. That is the way of the manufacturers and what is being made for todays dishwashers

  116. Great site! lots of good advise. I also had “pond water” in the bottom of dishwasher. So if you have one that is holding water, don’t assume its broken just yet, like I did. It most likely could be a plugged up dishwasher drain line. My unit would run until the water level float switch kept shutting it off to prevent a flood on my kitchen floor. It was doing what it was designed to do, by shutting itself off. I ended up completely removing the dishwasher drain line, took it outside and blew out some yukky stuff with garden hose water pressure. The original drain line was not installed properly which allowed food from disposer to back up into dishwasher line and clog it. Using a zip tie to elevate drain line right before connection with food disposer, will help to prevent clogs!

  117. Your picture shows braid covered tubing, next picture has unbraided PVC tied to the water solenoid. What up with that?

    • Hi Stu,
      My, you’ve got sharp eyes! Since hook-up vary for different dishwashers, we included photos from more than one dishwasher in the article to give readers a different look.

  118. our garbage disposal clogs the hose coming from air valve from dishwasher so when we run the dishwasher it runs out vent all over counter/sink. We wash by hand usually so it is not often we use dishwasher. I should not have to unclog that line every time i want to use dishwasher, there must be a way to prevent the disposal from pushing food into that hose?

  119. I’m installing a used Bosch dishwasher. The original water feed was through a copper tube. I’ve replaced it with a braided hose but the inner diameter of the hose is smaller than the copper tube. The dishwasher never finished its cycles. Could the inner diameter of the hose be a problem?

    While the guy I bought the dishwasher from said it worked fine, I really don’t know.

    • Hi Mike,
      I’m no appliance expert, but I would think that dishwashers would have to fill to a certain level in order for the cycle to begin, rather than relying on a timer on the water line. Otherwise, you would get more or less water in the dishwasher depending on your water pressure. If that assumption is correct, then the size of your pipe shouldn’t affect the cycle.

  120. Hi,
    I am going to install a dishwasher in my apartment. The water supply under the sink is made out of copper pipes. They are like a upside down T. The vertical part goes to the sink, the other part should go to the dishwasher’s water supply. This end is closed so I will have to cut it to open it. My question is: how can I connect the shut off valve to this pipe seeing that there won’t be any threads, or clamps?

    • Hi Dany,
      The easiest way to install a shut off valve on copper pipe is to get one that uses a compression fitting. To install, turn off the water at the meter, cut the pipe using a pipe cutter or hacksaw (keep a bucket handy to catch any water in the pipe), remove any burrs from the pipe, clean it with fine sandpaper or fine steel wool, slide the compression nut and ring onto the pipe, push the pipe into the shut off valve and tighten up the nut (don’t overtighten). The other option is to use a shut off valve that is soldered to the copper pipe using a propane torch. Good luck with your project!

  121. I’m installing a Dishwasher and am curious to a couple things: First, I’m connecting the drain line to an existing line directly below the floor. The instructions say to put an air gap in for such a case. I have consulted 5 home improvement store plumbing “experts” and 3 of them say that as long as it comes up the proper height, then down into a drain line that has a p-trap, it will be fine. Two have said to put in an air gap. I’m trying to avoid the air gap because I don’t want it sticking up through the countertop in my island. Can it be mounted within the dishwasher space and under the countertop to avoid visibility?

  122. My other question is, how far should the kickplate stick out from the rest of the cabinet kick area? To easily open/ close the door, it is sticking out at the bottom about 2.5 inches. I usually see it flush with the cabinets in the stores, but is that because they are different models?

  123. I recently installed a new dishwasher in a total kitchen renovation at our home and prepared first by reading through your site and found it most helpful resulting in complete success the first time around…Thankyou…what I did not expect was switching from a portable to a incounter dishwasher which either were not cheap brands/makes did not deliver equal satisfaction. New Models now require different soaps/cleaners too deliver the same results but are by far more quiet than older models…Miller time….


  125. Can a dishwasher be installed in an island with no sink. The sink drain is over 5′ from where the dishwasher would be located in the island. The drain line would have to go under the floor of the kitchen (no basement)and come up through the floor and then into the drain pipe above the trap. Will this work or should be install a prep sink (for the drain line to be closer) in the island? Also what is an air gap?

  126. I recently bought a 1994 Fleetwood doublewide mobile home. It has no dishwasher. The cabinet next to the sink from what I can gather is for a dishwasher. Can you give some advice on how to proceed? Electrical, plumbing…do I have to get a carpenter to remove the cabinet, an electrician for the electrical work and a plumber to install? Any help would be greatly appreciated.

  127. My Dad bought(several)dishwashers although we measured different sizes for each, all of them have been between 1/16″ and 1/4″ too tall

  128. *********WATER LEFT IN DISHWASHER!!! I havent seen this solution to the problem of water left in the dishwasher,But if the garbage disposal is not completely empty, the pump on the d.w. will not be able to work properly to empty the d.w. Try running the disposale befor useing the dishwasher.

  129. If your dishwasher is not draining completly your drain line for the dishwasher is probably clogged and not allowing all of the water to drain out. In other words the water draining from the dishwasher has nowhere to go because of a blockage in the drain so its coming back up into the washer… I would check the drain hose of the dishwasher for any blockages, and if thats clear maybe have the line that the washer drains to snaked out

  130. I’m installing a maytag dishwasher. The drain hose supplied with the unit is much longer than I need (it’s 6 feet). It cannot be shortened given the design. Can I loop the hose under the sink before attaching it to the air gap connection?

  131. How far should you push back your dishwasher when installing it? Is it ok for the dishwasher to touch the drywall behind? My problem is the space for the dishwasher is not long enough so If i leave about an inch behind, the dishwasher will protrude a little. Will there be mold or rotting problem if I push the dishwasher all the way and it touches the drywall behind. I am worried because dishwashers run really hot temperature. Thanks

  132. Have a portable dishwasher Danby 18″, .. I live in a building app.. Landlord said that peoples around get hot water wen showering and assuming is my dishwasher wen draining make hot water run into gold tab, some like that, so peoples around, get hot water from gold water tab, “that really confuse me” it’s , its is possible,” it’s a first time I heard of that”, Hope you can understand and help…. cause they want I get read of it or fixe permanent… its new PORTABLE dishwasher and I’m renting a bachelor small kitchen ..I don’t want do that … HELP

  133. Hi,
    I just installed a dishwasher and the connection to gargage disposer is leaking. I tried to tighten up as much as I can as well as well adjust the clamp too, still can not get rid of a small leak around the hose connection to garbage disposer. Any idea what I can do the prevent leaking?

  134. Danny, This is a Great source for info. Much appreciated! BTW folks, I’ve read each posting here and many if not most have been answered multiple times so it might be a good idea to read the entire web page before asking a question that has aleady been answered, and, you learn more by reading all the other posts 🙂

  135. Our dishwasher has water that keeps building up at the bottom when we wash dishes. We just moved into the house and are thinking the previous owner installed the dishwasher incorrectly. All of the hoses are down low under the sink and we read somewhere that said they should be higher up. Is that true? If so, what can we do to fix it?

    • Hi Leigh,
      While the hot water supply line can run down low, the dishwasher drain line needs to loop up above the height it connects to the sink drain to prevent backflow as discussed in the section on “Connecting the Drainpipe” in the article above. Some local building codes also require the installation of an air gap in the countertop or sink to further reduce the chance of siphoning. Good luck with your project!

  136. I’m replacing a dishwasher and was going to reuse its quarter-inch plastic supply line. But the new unit says:

    3/8” O.D. copper tubing with compression fitting or flexible braided water supply line NOTE: 1/2” minimum plastic tubing is not recommended.

    Is my quarter-inch supply line too small? Isn’t all the water pumped and not sprayed from the faucet.

  137. Thanks for the tips, I’m tackling an install tomorrow and was a bit nervous about the wiring portion. Your descriptions have me feeling confident again. Thanks.

  138. We just installed our old built-in dishwasher and the water is spraying both into the dishwasher but also all out the side of the dishwasher where the fill hose is… Any ideas on what is wrong???

  139. Just installed new dishwasher. Hooking up the drain connection, I noticed there is a small plastic sleeve on the inside diameter of the drain connector, that looks like a potential blockage. Instructions make no mention of the plastic sleeve. I pulled in out once but put in back in, Unsure…?

  140. Water coming out of the air-gap. I have installed 2 dishwashers in two different locations, one had no problems but the other keeps spilling out the water from the air-gap onto the sink. I asked a couple of plumbers and they said it has to do with either a clogged drain or the drain hose needs to be above the trap. New drains and both are above the trap. So my guess is that the one that is spilling the water is only 10″ above the trap and that might not be enough to let gravity take the drained water into the trap. If that is the case then there is nothing I can do short of tearing out the drain from the wall and lowering it. If there is anyone out there that has another opinion please let me hear it. Thanks

  141. When installing a new dishwahser in an older house that currently has a copper line as opposed to a wetal line. Will the valve connected to te coppper line be compatable with a metal line?

  142. My question is, what to do if the screws holding the dishwasher to the bottom of the countertop won’t stay in? We’ve been in the house for 6-years and the screws continuously come out. We’ve tried screws a bit longer and they still pop out. Now the whole is stripped. We don’t know what to do!

  143. Kelly; Carefully drill stripped holes with a 1/4″ drill bit, being careful not to drill through the countertop. Then , glue a 1/4″ dowel using weldbond or similar glue into hole, and cut flush with bottom of counter. Once glue is dry , you will be able to put in screws , and it will hold. I personally would pre-drill a small pilot hole before screwing in new screws.

  144. I just installed a Whirlpool dishwasher for my son. This model has a garden hose connection for the supply line. I used the old soft copper line (1/2 in o.d.) with reducer to connect to an elbow. This elbow has a gardem hose connection on one end with 3/8 compression on the other. When supply was turned on there were no leaks. About 5 min into the wash cycle the GH connection to the supply solenoid started to leak. I am thinking I should have used flexible hose connected to GH elbow. What is your opinion of what may be causing the leak.

    Joe C.

  145. bought a new ge dishwasher, will not go thru cycles, stays on wash. does not move soap around, just plops out, dishes do not clean at all, help!!

  146. I bought a kitchenaid. Salesman said I need at least 34 inches of hieght but I have 33 and 3/4 up to the dishwasher as I have installed a new floor (ceramic) but after that I have 34 inches possibly more. Will it still be able to be installed?

  147. I just installed a dish washer for my nephew. My first in about 8 years. He has Granit counter tops. I reminded him to be sure they put in the threaded incerts to mount the unit. they told him they don’t do that any more, to use the side mount holes. OK live and learn. but the holes are way too big. I used a screw and washer for a temp. fix looks like I need a large head screw with a gasket of some kind is there a special screw for this?

  148. I have a old dishwasher -installed in 1998- still works, but is not secure and when both top and bottom rack are pulled forward, the dishwasher tilts forward. There is no place on the top to secure it. Any suggestions???

    • Hi Handy Sue,
      You might be able to slide the dishwasher out a little and use short sheet metal screws to attach two pieces of metal pipe strap to the top of the dishwasher (don’t screw through the inner lining of the dishwasher), then slide the dishwasher back in and screw the other end of the pipe strap to the underside of the kitchen countertop. Small metal joining plates would probably work as well, if they’re the right length. Good luck with your project!

  149. I have an option to mount my (LG)dishwasher as a side mount but don’t have the screws to do so. Is their special screws for this and are their spacers available that go between the dishwasher and cabinet for these mounting screws.?

  150. Just had a new whirlpool dishwasher professionally installed to replace the one which was installed when the house was built. The new washer is not quite as wide as the old one and there is a half inch gap on the side between the cabinet and washer. What can be done to hide this opening?

  151. Good day,

    My wife wish to install the dish washer on high level, I mean to be installed 1 meter above the kitchen ground, is this correct ?, or this may cause some problems ?.
    Thanks to advise.

  152. we got a dishwasher for free its a whirlpool. it didnt come with any hoses or instructions.. what kind of hoses do i need to get?

  153. This website is great! I appreciate the details for installing a dishwasher in a house that didn’t previously have a dishwasher. I checked other sites but they were not as detailed for my needs.

  154. Instead of mounting to the counter top with screws. Once can also mount it through the floor. Many dishwashers have drilled holes on the metal feet for that purpose. Frigidaire ALSO HAS INSTRUCTIONS FOR THAT FORM OF MOUNTING AS AN OPTION. They suggest lag Bolts, However since our kitchen is open to the basement, WE USED 2 INCH LONG 1/4 INCH DIAMETER BOLTS,FENDER WASHERS, AND NUTS TO FASTEN IT TO THE FLOOR instead of the counter top. Very stable and quiet!


  155. After getting new granite countertops put in, the plumber broke the install brackets to my LG dishwasher. I need new ones. Any help on finding some? LG was no help.

  156. We had a complete kitchen renovation done, including having our old Smeg dishwasher installed under counter and plumbed in. Previously, it was on wheels and we would roll it to the sink and screw it to the tap installed under the sink.
    The new installation was done by a plumber who extended the drain hose. Does the drain hose need to be from a specific material? To me, what was installed looks like a clear reinforced garden hose.

  157. I am installing a dishwasher into my home. There is a spot for the dishwasher to go and I have all of the equipment to actually hook the thing up. I have looked at ALL the websites and still no answer to my ONE question, which is:

    The dishwasher has a plug, however there is no outlet where the diswasher belongs; just wires hanging out of the wall with wire nuts on them. Should I install an outlet, or cut the plug off, strip the wires, and install? Any suggestions would help. Thanks!

  158. i wanted to find out what training is required for installing chemical dosing units to commercial dishwashers / glass washers. i am fully qualified plumber.

  159. This may seem like a strange question, but we’re doing a kitchen remodel in our home. The dishwasher cannot fit near the sink and the sink is essentially on an island or short wall. There is a vent stack in the wall behind the proposed dishwasher area that has nothing draining into it (it was for the old sink). Would plumbing the dishwasher into the stack be suitable or is it required to be near a sink even if that’s not possible? Thanks for the help.

  160. G’day mate, installing d washer but no existing water inlet available without excessive cost/time, can I run a blueline hose from external mains under house to washer without a plumbers license?

  161. My kitchen sink has 4 holes, so I bought a new faucet set that would use the 4th hole for a pull out sprayer. My handyman says the 4th hole should continue to be used for the dishwasher thing that is already installed there in the 4th hole(for overflows?). I don’t recall ever seeing the mystery dishwasher thing do anything. Is it really necessary or prudent to keep it? The dishwasher is a very basic General Electric PermaTuf that was installed in 1987. Thanks for your thoughts.

  162. Installing new Kohler faucet with sprayer on Kohler cast iron/porcelin double sink. Sink has four holes,one which is used for the dishwasher drain air gap. If stalled,I don’t have hole for the sprayer attachment. QUESTION: Can DW drain air gap be relocated under sink as high as possible & strapped to cabinet wall, thus allowing the fourth hole to be freed up for my sprayer??? Will this cause any problems in DW drainage???

  163. A few months ago, we had a new dishwasher installed. Due to the layout of the kitchen, the dishwasher couldnt be installed flush with the cabinet. It would hit the fridge & not open. It had to be installed at a slight angle and the installers had to bend the brackets at the top in order to angle the washer to where it needed to be. We had to sign a waiver acknowledging that they were unable to properly install the unit. Well as it happened one of my kids fell onto the open dishwasher door one night & snapped the brackets. Now nothing is holding the dishwasher into the cabinet and the whole thing falls out when we try to load/unload the washer. We have to prop a box under the door in order to hold the dishwasher inside during loading/unloading. Is there a way to reinstall this? We dont have any brackets up at the top anymore. My husband wants to screw a metal bracket into the front of the cabinet and I wont let him. Please help.

  164. I have the answer to my November 16 question. No sprayer for me, because the local building code requires my dishwasher to have the air gap. Too bad. I like Sam’s solution, though. I’ll ask my handyman if it’s feasible to do that.

    • Hi Dana,
      Thanks for the followup. Depending on what type of countertop you have, you could drill a hole in it and put the air gap there, rather than on your sink, if that’s okay with your local codes.
      Good luck with your project!

  165. I see that you mentioned that the height of the opening is not a concern, yet the old dishwasher we want to remove is 33 1/2″ in a 33 3/4 opening and the new is 34″ with the installation manual asking for 34 1/4″ minimum. Do you think it will fit?

  166. installed a new dishwasher in our kitchen using this article. It did not have a dishwasher before and was a super easy install, but I have water coming out the air gap when the dishwasher is draining. I see that a number of people have posted the same problem, but no one has posted a solution. What can be done to stop the water from coming out the air gap? Please……….

  167. the dishwasher we purchased is smaller than the hole left from the previous one, what do we do to secure it properly and close the gap on both sides? (about 1/4 to 1/2 inch on both sides

  168. I have recently moved into a house that already had a dishwasher installed. I wondering what is wrong with the dishwasher it runs but no water is coming into the appliance was wondering if something is missing off the dishwasher and is something wrong with the dishwasher.

  169. Hello Danny — have same question as ‘Joe’ did, relative to a DW unit (Maytag MDB8859AWS2) with controls AND VENT on top of door — just read entire list of Q&As and did not see Joe’s inquiry addressed — am assuming that those control buttons AND THE VENT should be visible from above when the door is shut (please confirm or otherwise please let me know) — Thanks Danny — Matt 2/26/12. Joe’s earlier inquiry follows:

    Joe Says:
    January 19th, 2010 at 9:09 am

    I have cut out a 24″ cabinet. Under the cabinet was not tile as their is in the rest of the kitchen. I placed 3/4 plywood down to make sub floor level with the tile. I have all electrical and plumbing complete but the dishwasher is having fitting issues.

    I have a Kenmore with top mounted controls. Are these controls to be visible with the door closed or must they protrude out from the counter top and be visible with the door shut?

    I do not seem to have any room to screw in the top metal secure latches. My counter top is laminate and it has a lip that lowers. Right now the controls on the top of the door are visible when shut. Does this need to be pushed further in? When I do push it in the door gets caught on the counter top. How much of a gap should I have from the counter top to the inside top of this dish washer?

    I thank you for any advise you are able to provide.

  170. true, but the age old question of Why does the vent spurt water has not been answered yet and it has been asked numerous times………

    • Hi Bud,
      There are a number of possible causes for water overflowing out of a dishwasher air gap, here are some common problems to check and fix if needed:
      • Check to be sure the smaller (5/8” I.D.) inlet hose goes from the dishwasher to the small inlet on the air gap, and the larger (7/8” I.D.) outlet drain hose goes from the air gap to the sink drain and/or garbage disposal.
      • Check to be sure there are no kinks or sharp bends in the drain hose from the air gap to the drain/disposal and that the hose is as straight as possible.
      • Check to be sure the outlet drain hose isn’t clogged or restricted in any way.
      • Check to be sure garbage disposal and/or sink drain aren’t clogged and drain easily.
      • Check to be sure the sink drain is vented properly.
      • Check to be sure the cap on the air gap is installed properly.
      Hope that helps,

  171. Really? Where is the information concerning the vent on the top of the door being blocked by the countertop? Proper venting is needed for both dishwasher performance, and so that steam does not ruin the countertop. People have rationalized the placement of the control buttons, but how does one explain the placement of the vent? Someone–please let me know! Thanks!

  172. Hello! Most DW doors have THE STEAM VENT (not talking here about anything related to the discharge hose) on the front of the door, to release steam — the Maytag MDB8859AWS2 has its button controls AND STEAM VENT on TOP of the door! 1.How can it make sense to install the DW back into the cabinetry so that the top of the door is against the underside of the counter top, thus COVERING THE STEAM VENT? 2.Please point to where this question has been asked and answered, if that is in fact the case. Thanks — Matt

  173. sorry, I didn’t mean vent, but discharge hose, I have read the entire set of posts and no one has been able to answer why the “vent” on the discharge hose spurts water.

  174. I replaced the old dishwasher with a new one and now the hotwater won’t turn on theres cold water going to the dishwasher but not the hot any suggestions

  175. Tonight I am replacing a compact dishwasher with a regular size one. My water supply is pex, and I need to be able to clamp a rubber hose to it for water in take…will I be able to purchase the same size hose in rubber. Also, can I just attach the drain hose to the inside of the cabinet to raise it. My other dishwasher used gravity to drain, so this wasn’t an issue.

  176. We installed a Frigidaire dishwasher under a granite top. we used the side mount kit. The kit has brackets which screw into the cabinets on each side with one small screw. After minimal usage, the cabinet wood split at the site of the screw. It seems like a lot of weight on this screw once the door is opened and the tray full of dishes is rolled out. After repairing the damage how do we prevent this from happening again.

  177. Holes for side mount must be predrilled or the wood will split,you need to ues 1 inch sheetrock screws and predrill the holes for them,the longer screws will get you into good wood

  178. I am installing a portable dishwasher and making it permanent. Is there a valve to keep drain water from running into the dishwasher when not in use?

  179. Iam installing a dishwasher next to a wall to the garage. just the other side of that wall is my washing machine. Can I tap into the washer drain or try to run the drain about 10 feet to get under my gardage disposal?

  180. I am about to install a new Westinghouse free standing dishwasher under bench. Can you please tell me if it can be connected to the instantaneous gas hot water system OR does it have to be cold.

  181. HELP!!!
    Recently my water supply line on my dishwasher split, I had it replaced and within 30 minutes it split again, it was replaced again a week later it split yet again.(I’m using braided steel line) I was told my water may too hot, true or false? What other problem could it be.

  182. I’m installing a new dishwasher and have discovered the wiring does not match up. The house has black, white, red and a ground. Dishwasher has black, white and ground. Can DW be connected using this wiring?

  183. If you are going for best contents like me, simply pay a quick visit this website all the time as it presents quality contents, thanks

  184. Just had an old dishwasher replaced with another of the same manufacturer (GE). I had to clean out the undersink cabinet before they came. They were here quite a while, most of the time under the sink. When I started putting things back, they had removed the copper water line to the dishwasher and replaced it with a plastic tube. Why would they need to do that?

  185. We are installing a new Samsung dishwasher. It has a black gasket around the door, and we can’t tell if the dishwasher should be pushed back in the cabinet enclosure so that we don’t see the gasket outside, or if the gasket stays outside of the enclosure, thanks for your help.

  186. I have just purchased a Samsung Dishwasher- I want to know if I don’t want to place it below the slab-top and want it to get installed some hight as I have old parents and they can’t bend to place things. Can I give it a height of 36″ (3ft) from floor. waiting for some expert advice.

  187. Is it a good idea to install the dishwasher at a slightly higher height than the floor. This will avoid the bending down and might make it easier to use (especially for us older citizens). If yes, what should be the platform height. Will there be any additional things to look out for if I decide to do this? What could be the possible disadvantages in doing so?

  188. I recently purchased an new dish washer and paid to have the contractor, American Home Service, install the dishwasher at my home, which is a rental unit. I was not present at the time the installer came to my house. They told my renter that there was a problem with the hard wiring that is would not reach and that a welder would have to install a shut off valve, based on the age of the pipes that are there, and are connected to the dishwasher that has stopped working recently. My question is this, why can’t the company that i contracted to install handle the installation. I’ve paid for the installation of this appliance. Unfortunately this company doesn’t have the qualified installers to complete this job or any other job which requires just not pull and plugging something back into the place that they took the broken appliance from. Should I contact a plumber and a electrician. American Home Service will gladly install after I make this necessary shut off valve and electrical wiring easy for their installers. Is it necessary to have a shut off valve installed, and who should I get to do it? Yhe company tells me they can’t and won’t recommend a welder or electrician. I am located in Baltimore County Maryland. Thanks for any input you can email to me.

  189. I just installed a Frigidaire dishwater after removing old one.
    PROBLEM: The so called “screw” instead of a phillips scew, ended up being a rivet…I determined that it was a “pivot point” to rotate the cover downward in order connect electrical source. The rivet was so very that I had to PRY open the connection box. When a rivet is used it should allow easy since the snap end cover will keep it closed after wiring is completed.

  190. I bought a portable DW for a temporary rental home to take when I move. Now I’m considering using an installation kit to convert it to undercounter & shorten cord to just the length needed to plug in. If I do this, would it be possible to change it back to portable, or easy enough to detach when I move?

  191. We have a 2 drawer dishwasher in an island bench, it is situated at the end of the island with a stone waterfall edge! It tips forward when you open the drawer. how do we fix it?

  192. Hi, we are remodeling a house and ordered brand new appliances! But my idiot contractor keeps doing all kinds of things either sloppy, or just plain wrong. This time he flipped the dishwasher upside down while it is still in the box. Presumably to connect the plug wire. When I said you don’t do that, I got a typical smart alecy response. So I flipped it over and opened the top of the box WHICH IS SATURATED WITH WATER!!! Is the dishwasher going to be okay??? Or should I just return it???

  193. This is a great post about dishwasher installation! I have been looking various places for a new dishwasher, but I never thought to check if the new dishwasher will fit in the old one’s space. It’s a good thing I saw this post, otherwise I might have made a really big mistake! I know that some kitchen appliances can be returned if there was a problem, but I would much rather avoid the hassle in the first place.


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