What about a presure relief valve? if your faucets are closed, and you have a check valve from your tank... that could become "explosive".. the heated water creates/builds up presure, and nowhere to go.
Dont get me wrong, I like the idea very much, but looking at the safety aspect of it in addition, and what can be done to mitigate any accidents. Unless your using it as a pre heater for a HW tank (then you might need 2 chck valves...dunno)
Last edited by jbrodgers; 02-16-2011 at 11:12 AM..
Reason: additional thoughts