Standard Water Pressure
Water coming into your home is measured in pounds per square inch and usually ranges from 35 to 100 PSI. The happy medium is somewhere between 40 and 50 PSI.
When water pressure is very low, faucets may trickle, and some appliances, like water heaters and icemakers, won’t work properly. When it’s very high, you might hear pipes banging; in extreme cases, lines can burst and flood your home.
The solution for these issues is a global valve, which regulates water pressure and allows you to adjust them to acceptable levels. First, check the water pressure with a gauge that screws onto an outside faucet. These are available at most hardware centers. If the pressure isn’t acceptable, it might be worth talking to a plumber about installing a global valve to regulate your water pressure.
How to Test Water Pressure
The easiest way to check your home’s water pressure is to test the incoming pressure from the municipal lines.
- Locate the first faucet along the incoming water line. This faucet has the highest pressure and will tell you if any pressure issues are in your home or originate in the municipal lines.
- Make sure there is no water being used in the house. If you plan to exclude those from the test, you may use individual shut-off valves for faucets or toilets.
- Close the main shut-off valve.
- Attach a water pressure gauge to the faucet.
- Turn on the faucet completely to get a reading of the pressure.
You may test other faucets in the home using the same method to help locate pressure issues within the home once you have an idea of the initial pressure rating. This is especially useful for cases where you need to have a plumber check the pipes, as it provides a much smaller area to search for the source of your pressure problem.
Existing Plumbing Pressure Test
Using a water pressure test, it is relatively easy to test your plumbing for problems. An alternative is to test using air, generally reserved for new plumbing. You will need an air compressor and an adaptor to connect the compressor hose to a threaded faucet. To test using air pressure, you will need to do the following:
- Locate the main shut-off valve and turn off the water supply.
- Run your faucets to drain the pipes, and make sure all are turned off again once the pipes are empty.
- Attach a pressure gauge to a threaded faucet. This might be one in your laundry room or outdoors.
- Attach an adaptor to another faucet and connect your compressor hose.
- Charge the system to a rating of 60 psi and wait 15 minutes.
- Ensure the pressure has not dropped (indicating a leak) before turning the water back on.
New Plumbing Pressure Test
Testing new plumbing using air is more complicated than testing existing plumbing, although it can be much more effective. You will need some balloons and test weenies, which are inflatable devices with pressure gauges attached. Test kits may be purchased, or you may purchase the individual components from a hardware store.
- Block all drains, vent pipe fittings (DWV lines) and toilet flanges using the inflatable test balloons. You will want to insert them into the T-fittings before inflating.
- Glue test caps to the end of all stub-out pipes. These pipes protrude from the walls or floor for later fittings to be attached, such as a shower head.
- Locate a clean-out fitting and inset a test weenie. Be sure the gauge is upright and easily readable before inflating.
- Bring the pressure within the pipes to five psi and wait 15 minutes, checking occasionally for any changes in pressure.
If a leak is suspected, you may use colored smoke or listen to the pipes for hissing sounds that may show a leak. Alternatively, you can place diluted dish soap on the joints and watch for air bubbles.
Low Water Pressure
Low pressure can be quite frustrating. Not only will it trickle your faucets and slow down your washer, but it can also lead to issues with your toilet or indicate a major problem. Thankfully, low pressure is often easy to diagnose and treat without professional assistance.
What Causes Low Water Pressure?
There are many potential reasons for low pressure, many of which are easy fixes. Here are some of the more common problems:
- Single Faucet: This is often caused by debris in the filter screen. There is usually one located at the end of the tap and sometimes another inside the base. Rinse and wipe out the debris to improve the water flow immediately.
- Shut-Off Valves: A common culprit of low pressure is a main shut-off valve for the entire home and ones leading into your toilets, sinks, etc. They can restrict the water flow, reducing pressure if not fully opened.
- Pressure Reduction Valve: Some municipalities supply water at high pressures, and your home may have a pressure reduction valve installed to limit the incoming water pressure. The factory default is usually 50 psi, but may have been set lower by a previous owner or is too low to supply a larger home properly. Adjusting the settings will often alleviate the problem.
- Leaks: Low pressure can be a sign of leaky pipes. Perform a pressure test and watch the gauge for signs of a leak. If the pressure changes, you may need to hire a professional to locate and repair the damaged pipe.
How To Increase Low Municipal Water Pressure
In some cases, you may discover that the water pressure is low due to the municipal lines. Such problems usually also affect your neighbors and will require the installation of a water pressure booster. This device consists of a pump and pressure tank installed near the water meter.
A dial allows you to adjust the pressure between 45 and 55 psi while the tank stores extra pressurized water to reduce how often the pump must run. Pressure booster systems may be expensive, often running $900 or more, but they may be the only solution to low municipal pressure.
High Water Pressure
While low water pressure is a nuisance, high pressure can be a nightmare. It can lead to burst pipes, boilers or water tanks, leaks, and associated problems such as flooding or mold. There are several warning signs of high water pressure, and you should test the psi rating if you encounter these:
- Turning a faucet on or off causes banging or other noise from the pipes.
- Spitting and leaks coming from faucets.
- Toilets sometimes run when not in use.
- Higher water or sewage bills without increasing water consumption.
The latter sign occurs because more water is used in the same time as lower-pressure pipes. Thus, running a tap while your water pressure has a rating of 150 psi may use two to three times the amount of water it would if the pressure was only 50 psi.
What Causes High Water Pressure
The most common cause of high water pressure is municipal supply. Depending upon the requirements in your area, the water company may need to deliver water at a high-pressure rating. This is especially true when they must service tall buildings or areas high above sea level.
Another possible cause is thermal expansion. High temperatures in your home may contribute to heating up the water pipes to a small degree. Additionally, your water heater will cause the water to expand slightly. The hotter the water, the more pressure it will exert on the pipes. For this reason, it is always best to keep your water heater set at a low to moderate temperature setting.
How To Decrease Water Pressure
When faced with high municipal water pressure, installing a pressure reduction valve is the best solution. This valve connects where the water enters your home and reduces the incoming pressure. It is generally factory set to 50 psi, although you may adjust the pressure setting to allow for a higher psi rating.