Originally Posted by chrisr
yep...might be easier...
I went through that in a house I owned. Was in a high water pressure area (read AT sea level) and so had a regulator
on the water main. No backflow when the water heater
kicked on. After the second heater
failure and lots of water on the floor from the overpressure relief valve the light went on. An expansion tank.
Iíve seen that on a couple of boats Iíve owned.