Tankless hot water heaters, such as those made by Rinnai, heat water as it passes through the unit to provide a continuous supply of hot water on demand. This allows you to fill large soaking tubs without running out of hot water and can be useful for hydronic air heating, unlike traditional tank type water heaters which have a limited amount of hot water available on demand.

Watch the video above to find out more.


Danny Lipford: If you have your heart set on a large soaking tub like this, here’s something you need to think about. Now, if you have a traditional water heater that’s 30 or 40 gallons, and you have a tub like this that can hold as much as a 100 gallons, you’re not going to have that nice, relaxing hot bath that you had planned.

I hear it from homeowners all the time complaining about their large tubs just simply not getting warm enough. I never hear that complaint from any homeowner that has a tankless water heater.

Artie McGowan: The biggest advantage with a tankless water heater is that you don’t run out of hot water. You got a conventional tank, 40 gallon, and you’re trying to fill a tub, you got several people who want to take a bath, you’re going to lose hot water. Somebody’s going to take a cold shower, and nobody likes that. So, Rinnai, the tankless water heater, gives you a solution that is great for the family.

What happens is, as soon as you go to your valve and you turn it on, it’s got a flow switch inside of this here. When that water goes past that flow switch, it says, “Turn on the heater.” The heater turns on, it continuously heats water whenever you need it, at the time you need it.

What I like to do to with Rinnai is, turn on your heat, take your digital control, and move it down to 104 or a 106. Go to that big large tub that you want to take a bath in, simply turn on the hot water side.

In other words, why have water at 120 degrees, coming into the bathtub, knowing you can’t get in there, and then have to cool it down on the cold side, by delivering some cold water with it. So in this case you just turn on the hot water valve and just fill it up.

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Danny Lipford


Danny Lipford is a home improvement expert and television personality who started his remodeling business, Lipford Construction, at the age of 21 in Mobile, Alabama. He gained national recognition as the host of the nationally syndicated television show, Today's Homeowner with Danny Lipford, which started as a small cable show in Mobile. Danny's expertise in home improvement has also led him to be a contributor to popular magazines and websites and the go-to source for advice on everything related to the home. He has made over 200 national television appearances and served as the home improvement expert for CBS's The Early Show and The Weather Channel for over a decade. Danny is also the founder of 3 Echoes Content Studio, TodaysHomeowner.com, and Checking In With Chelsea, a décor and lifestyle blog.

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