I am having a Rinnai tankless gas unit put in to replace my 40 gallon tank which is now over 12 years old. I am building a game room in the basement and the last thing I want is a flood. I also do not see the logic in keeping 40 gallons hot even when we are not home. The price of gas is on the rise and not expected to drop any time soon. We are a family of 4 and the price of a Rinnai versus a new tank with power vent was not huge.

 

There's a guy I know of on the Explorer Forums that has a tankless on-demand hot water heater. He swears by it, being on an all-electric setup where he lives, but the thing is 23,000 watts at full-draw (there are three stages)..... My puny generator is 5500 watts.... that's not even enough to run ONE stage, let alone all three.

If it's hot water you need during a power outage, there's no substitute for natural gas. I've found that most of the pilot-less on-demand systems are forced-air exhaust, which, of course, require electricity to run teh blower before it'll fire the burner. Not a biggie if you have a back-up genny running. Standing Pilot units use *slightly* more gas, but don't generally have a blower for the exhaust. It seems to be a trade-off.

One more thing to look at is the venting and air intake on the gas units. There can be some issues with getting combustible air into the unit, and exhausting the fumes.... there are a lot of standards that have to be met on them.

I still haven't found one of either type that'll work well for me. I'll probably end up with a 75-gallon natural gas with a standing pilot. I just can't justify the cost of the tankless one I need to get to run my house....

-Joe

 

I did a search on tankless water heater thru Google looking for electric water heaters. This site has quite a few. Cost is under $1,000 US. They al require 220 volt and the top of the line for whole house takes a 120 amp circuit breaker. My 40 gallon electric only takes 50 (2 25amp). Of course it isn't trying to heat the water instantly.

http://www.gotankless.com/products.html