I do not think so, but I am not fully knowledgeable in the terms. All I know for sure is that it replaces your normal 40 gallon or whatever water heater with a tank less unit that after a minute or two you get hot water and you don't run out of hot water until you stop the water from running. My uncle said it paid for itself after a certain short period of time.

Reading some pros and cons to it and one person said one con is when you lose power, no hot water. Who the hell is taking a shower with no power? But it is a good point regardless. Apparently they aren't as solid as I had perceived.

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Feel your pain with girls. My twins are 14 going on 25.

A tankless water heater is not a boiler. And you are correct, it replaces a traditional 40-50 gallon water heater. And they are more energy efficient, because you are not heating the standing water in the tank while it is not being used. Though on average it takes about 7-8 years of savings to pay for the higher price. If you put two in, double that.

Another option to save money with either type is to have a staging tank in the basement that is letting the cold water warm up prior to going into the water heater. Every degree warmer going in, is less energy needed to heat. but that only helps if you are not actively heating the area around the water heater.

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I have a 65 gallon water heater and have never run out of hot water. Waiting 8 years to recoup the extra cost seems a little long to view it as an economic advantage, unless it's deductible on your Federal taxes.

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