Rinnai tankless water heater -

RV water heaters are so small that I don't see the advantage of a tankless and wonder why the OP wants one.

It only takes 10 minutes for my tank to heat 8 gallons up to very hot for a shower with outside temps in the 40's. I have an electric element too and have it pre-warmed. In ambient temps around 70°F, it only takes 5 minutes. I only run my propane just before a shower and leave it off all the rest of the time, the electric element heats it enough for the dishes or the occasional need for hot water to wash face or hands.

I would say that they aren't approved for use in a rv. They probably haven't been tested to meet the standards necessary for a rv. The lodge model is a horse of a differant color than a rv. I liked them and they were the top recommended tankless water heater to install n houses when I was plumbing.
Ron

My first thought was that the internal workings of the Rinnai may not hold up to bouncing and jarring that comes with being placed inside a MH.


Doug

Search this Forum for `tankless' and read on. Many complaints about adjusting the water for the shower. The tankless apparently needs a certain amount of flow to function which is more than the typical shower, unless one turns on the water full blast and leave it on. This, of course, will fill up the Gray Tank quickly and use up the Fresh Water just as fast.
Based on what I've read on this Forum they don't work well in an RV.

Should work, I have a Rinnai in my boat with no issues.

Reasons?

1. IF the Rinnai states to NOT install in an RV, That is the reason
2. MOST residential type tankless require at minimum a 1/2 inch gas line. Almost NO RV's have a 1/2 inch thruout the RV. The feeds are 3/8 copper line from a 1/2 inch line.
3. The specs for install almost preclude this Heater from fitting safely in most RV's
4. Last, the venting requirements would be very difficult to meet in an RV Doug

I think they have to have 220 v.

It might have to do with the 120 volt power supply, not in most RV's while dry camping, and the lack of ability to run the system on a cold night. Many will turn on at 35F to keep it above freezing.

You can plan on installing a drain adjacent to the unit to completely drain the water heater before driving on a freezing day. Even driving will bring a lot of outside air through the heater, completly freezing the water solid on a 30F day. This can burst the pipes, and of course freeze damage is not a "Warranty defect". Also if the unit does try to cycle on while in a moving RV - who knows where the flames will go or get pushed by wind? So if it has not been tested, I would not allow it to go into a RV if I was the designer.

Maybe they have tested them, and the compartment got to warm around the heater while driving the test RV.

Fred.

I loved my Rinnai, in my old house. The only thing I can think of is they may not make one small enough for an RV Or you may not be able to properly vent it, or be able to get the required propane volume. Mine had a 3/4" line running into it. It may be a liability issue with Rinni. Lots of possable reasons.

Don't have an answer for you as to why but I have a Rinnai in my home and love it.