Posted By embie on 11/15/2007 1:38 PM
I have never before specified one and cannot discern from my research if it is desirable to have a boiler to supply the system and then a seperate water heater for other hot water needs.
I believe I read somewhere that using a vanilla water heater to supply the hydronic will wear out the heater.
Can a boiler also be used to supply the other hot water needs?
Last sentence: Bingo! Get a modulating/condensing boiler and a 'sidearm'(indirect WH). The 'sidearm' acts as another zone, usually has priority, and will provide all of your DHW needs. You can size your tank to your needs(40, 60, 80 gallons)
I would avoid a standard WH for efficiency reasons, it's ability to 'recover', and you certainly don't want an 'open' system.