Locating a Tankless Propane Water Heater

[Birkoff]

Last year I had a 500-gallon propane tank and a Rinani inside furnace installed in a small cabin in the Oregon Cascades, which is vacant most of the time. Works great. The heating cost were cut in half from electricity.

Next project is to replace the electric hot water tank which is located in the corner of an attached single garage, which is located next to an entry stairs into the house (the lowest, coldest point of the house).

So my $64 question is, would it be better to install the tankless unit in the garage (where the electric tank is) or essentially put it very close inside the house. Installation would be a little more complicated, with a little more plumbing work and venting work, but the unit would be at about 45 degrees F in the winter, as opposed to the garage which does get colder, typically 35 degrees. I'm a concerned the tankless unit could be subjected to cold, possibly freezing temperatures.

I've read that tankless units can have a 'heating element' so they don't get too cold, but don't know anything about it. Installation would be by a plumbing/propane company who did the furnace.

Any advice and suggestions on the install would be appreciated.

 

[Twowaxhack]

It’s up to you. The units have freeze protection but must have power and gas to operate the frost protection.

 

[wpns]

I'm a concerned the tankless unit could be subjected to cold, possibly freezing temperatures.

Have them install it with a couple of extra valves to make draining it easy, then leave it empty when you are not there.

 

[fixitron]

You did not note whether you shut down the cabin when not in use. It appears that you keep the heat on at 45 degF? What happens when the heater fails? Will the pipes freeze? I would stick with the electric tank. A tankless would cost much more to install, but for occasional use in a small cabin means that it will not see much use, and is still subject to freezing. A propane tankless heater is much more complicated and will cost a lot more for installation, maintenance and repair. The occasional use in a cold climate could also shorten its life. A tank is easier to drain, costs less to install and maintain.

 

[Birkoff]

Thanks for the replies. When not there I keep the inside of cabin at 50 degrees. There is a 4 foot crawl space under the house and pipes sit below the insulation. I think the crawl space stays at about 40 degrees even when its freezing outside. The garage gets colder. I've only had a frozen pipe once when it was -20 and a crawl space vent wasn't closed. I drip the cold water during the winter months in bath and kitchen.

I think I'd save about $300 a year in electricity when the tank is just sitting there. I've had the cabin for 30-years. I'm thinking the cost of tankless and install would be about $1500 to $2000.

 

[Twowaxhack]

You could just drain the tankless when you leave. The valve kit makes it simple to do and all you need is a 5 gal bucket or a pan drain.