My wife and I moved to Michigan from Arizona 3 years ago and purchased a 3000 sq. ft. home that has a gas boiler with baseboard heating throughout. Never having this type of heating we absolutely love it. The house, however, is just over 20 years old and our gas bills are rather high. I called a contractor to see what our options were and he threw us a curve ball that sounds great in theory, but I have never heard of anyone else doing. He explained that we could do away with our gas boiler and water heater, and go with a tankless water heater for everything including heating our home. Now, I have thought of using a tankless water heater (renai, actually) to help reduce our gas costs, however, using this system to run my heat? I don't even know if it has ever been done before. If it does work this could be an even more energy efficient way to go than getting a new boiler and tankless unit combination.
I just don't want to be stuck with the bill of having to install another boiler if and/or when this "idea" doesn't work.
I just needed to bounce this thought off of others to see what you think.