Tankless water heaters

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.
See posts with no answers
M

mphy98

Well-known member
Joined
Jun 30, 2008
Posts
244
I don't know if this has been covered here before, but has anyone ever put a tankless water heater into a class A?  This seems to make a lot of sense to me, and having put one in our shed for our kids waterslide before, I know they do not take up much space. Probably less space than a 6gallon Atwood.  any thoughts? has anyone done this?  I like to take showers in my own unit rather than the Canadian grounds when we go fishing, and we take turns with the 6 gallon one now. :)
 
What little research that I have done on this type of water heater is that they use very high amperages, if they are electric. The amperage draw can very easily go beyond what your MH is capable of. When you have such huge amperage draw you must have  large wiring to support the current.

I am not sure about gas heated ones as I did not research those.
 
Tankless water heaters have been used in some homes in  Japan for years.  They don't take up much space as mentioned but I have never seen any that I feel would support a shower that are smaller than a 6 gal Atwood.  You do have to make sure the temperature rise is sufficient for your needs.
 
Most housing in Spain is and has been using tankless butane/propane on demand water heaters for 30+ years. Not sure why this has not caught on over here in the USA quicker. I see some new home construction with these being installed, but it still does not seem to be the norm. With proper installation I don't see any reason why one of these could not be used in a TT or MH. The one I had in my house in Spain was approx. 12" wide, 10" deep, and 24" tall,  hung on the kitchen wall, and as long as I had butane/propane I had hot water. Much more efficient in my eyes than heating a large tank of water that may or may not be used anytime soon.
 
We used both gas and electric types in the UK over 30 years ago. As Jerry suggested, the electric type typically has a 3KW heater, which translates to 30 amps.

There have been prior discussions here in the past. Try using the Search function above.
 
Tankless water heaters was about all I saw in Japan in the early 60/s.  They are mose diffenately more economical.  We were considering having one installed when we were in TX.  Might even do it here in Montana.
 
Tankless heaters work fine but you need a good electrical supply for one big enough to support a shower. If you are willing to limit yourself to campgrounds with 50A service, you could probably get by.
 
Last spring when we had to replace our water heater in the house, I priced out several tankless heaters.  I don't remember the exact figures but I figured I would be replacing it before I broke even with the fuel savings.
 
The small TT my parents had when i was a child had a gas one installed from the factory I think it was a CREE. that was in the 60's.
The electric one i saw on ebay weren't that expensive but i don't know if it would support a shower either. Also they require 30 amps and up.
 
We had a tankless hot water heater (propane) installed in our new house.  We LOVE it.  We use far less propane and have an endless hot water supply.  It's not very big: 12" x 24" x 4".  I'm not so sure this concept would work in a motorhome using electric as your energy source; but a propane unit might be feasible.  I would think if the economy rebounds and manufacturers get back into producing lots of new coachs, you might begin to find tankless units, or a modified variation, in new coachs.

Marsha~



 
Marsha/CA said:
We had a tankless hot water heater (propane) installed in our new house.  We LOVE it.  We use far less propane and have an endless hot water supply.  It's not very big: 12" x 24" x 4".  I'm not so sure this concept would work in a motorhome using electric as your energy source; but a propane unit might be feasible.  I would think if the economy rebounds and manufacturers get back into producing lots of new coachs, you might begin to find tankless units, or a modified variation, in new coachs.

Marsha~
Click to expand...

We're trying to build a moderately energy efficient house - so water heaters have been a critical area of research.  We decided on a passive solar system with an electric back up... But the instant-on heaters were considered.
As noted above, an electric unt requires significant watts.  It's not just the amps required - but the voltage also.  Typically these water heaters are 220v and 30A - or over 6000 watts.  To run anything else in conjuction with the water heater, you're talking about a generator that can produce 8000 watts.  We're also talking about RVs that have 50A (220V) service.  110v 30A service probably isnt' enough.

I like the idea of propane, but the venting requirements on these furnances are significant.  You're burning a lot of fuel to cause that water to go instantly hot.  Providing enough space for that kind of heat is problematic.  Because existing propane heaters don't burn nearly as much fuel, they can be more compact and require less insulation.
 
Electric tankless water heaters are available for voltages from 110 to 277. Of course, for a given power (watts), the lower the voltage the higher the current (amps).
 
The question was about instantaneous heaters in an RV, not in a home. Apples and oranges. Everybody is talking about home installations but no one has answered his question about RVs. I would like to know too but I have found that my 10 gal DSI gas/electric hot water heater is adequate in the RV and almost instantaneous. Don't know of there would be any benefit to retrofitting in the RV.
 
Bruce,

The electric tankless water heaters I'm talking about could be fitting in an RV. But, as several folks have said, they will draw a lot of current, e.g. 30A for a 3000 watt unit on a 110 volt line. I haven't researched whether there are lower power ones available but, if there were, they would translate to either lower temperature or lower flow to maintain the same temperature.
 
This web site discusses various brands, and it appears that some are available with lower power heating elements.
 
Yes Ron, it all comes down to BTUs, and you can't beat propane in that department. However, not having researched it, I don't know if they make small propane tankless water heaters that would fit in an RV.
 
I actually saw on on a 5ver trailer that was mounted on the outside of the trailer outside of where I suspect the original water had been installed.
 
wow, lots of input, i was thinking about a propane one if it would fit in the standard hole for the Atwood.  i don't know if they make such a thing, but i would suspect that there would be a huge intrest in a standard conversion.  i know heating a tank is a waste, and two people cannot shower in a row without a 15 to 20 minute recoup time, so if any tankless mfg's out there are listening, let us know.  also the coach mfg's are watching this, i think this would be a great option for a propane not electric as a lot of campgrounds do not have high enough amp service. thanks for your support. bob
 
Sam & I have never run short on hot water while in the RV even when we had 6 gal water tank and we frequently shower within 10 025 minutes of each other.  But there would be some benefits to a tankless water heater.
 
You must log in or register to reply here.

Latest posts

Members online

Total: 851 (members: 29, guests: 822)

Forum statistics

Threads
131,966
Posts
1,388,388
Members
137,718
Latest member
urnwholesaler
Back
Top Bottom