Quote Originally Posted by Erni View Post
I've been thinking about adding a second water heater as a water storage device. Just hook the water in before the real heater and don't hook up the gas. The water gets cycled everytime you run hot water. Easy 50 to 75 gallons.
I recently saw a dual set-up like that. One of the tanks rusted out and burst, dumping all the water onto the sub-floor in the basement. Both water heaters and the furnace were all located in a line above a single floor joist. The weight of the full water heater, above a soaking wet floor caused the floor joist to warp and the water heaters to start to lean like they were going to fall through the sub-floor. Just something to keep in mind when you look at how to mount them, as water weighs approximately 8 lbs per gallon.