water heater help

[dafatman]

hi, i have a Atwood EHM6-SM 6 gallon water heater in my rv and it has the heat exchanger on it and i think its over heating when i drive long trips (like 500 miles in one day) first thing i found is the high temp reset was popped and when i turned on the water pump when i stopped the water was running out the pop off valve, SO does anybody know why this would happen? could it be possible that the high temp switch AND the pop off are bad? i "think" this water heater is a marine heater but i dont see what that would matter, do you? thanks

PS: its in a 2000 MH

[dafatman]

yes il replace it with a good one some day, as for now, ive had it running on AC all day and it hasnt popped anything i ran some water and it kicked back on so it seems if i leave the valve off from the engine antifreeze all will be fine till i can replace it.... thanks

[Darrah]

Sounds like you should replace the water heater with something that can actually handle it.....

Just an opinion, nothing more.

Good luck!

[dafatman]

drsolo wrote:

dafatman wrote:
ok got it figured out!!!
the heat exchanger is pumping too much hot water from the mh engine into the water heater and popping the pop off (over pressure) and its getting too hot so its popping the over heat reset too,,, 😞 so now i have to figure out how to cut the heat coming from the mh engine to the tank, i know i can turn off the valve coming from the mh but then i wouldnt have any hot water on the road, thanks

The heat from the engine is "free". Will the engine cool off properly without circulating to the heater and only to the radiator? Can you conveniently just hit the reset button when stopped?

the old owner had the valve shut off (because of excess heat in the motorhome going down the road) he says... me thinks he was lying LOL.. and ive drove it all over with the valve off and the mh was fine, yes i can get to the reset if i leave the cover off the front of the heater (its under the counter so it will be ok like that) BUT the pop off valve blows off going down the road and if the water pump is left on it will empty the fresh water tank 😞

what i think i might do is when im about 25 or so miles from my stopping point is to open the valve and pre heat the water in the tank... thanks

[drsolo]

dafatman wrote:
ok got it figured out!!!
the heat exchanger is pumping too much hot water from the mh engine into the water heater and popping the pop off (over pressure) and its getting too hot so its popping the over heat reset too,,, 😞 so now i have to figure out how to cut the heat coming from the mh engine to the tank, i know i can turn off the valve coming from the mh but then i wouldnt have any hot water on the road, thanks

The heat from the engine is "free". Will the engine cool off properly without circulating to the heater and only to the radiator? Can you conveniently just hit the reset button when stopped?

[dafatman]

ok got it figured out!!! sorry to waste time and space here....

Skip its electric and heat exchanger only.


here is the trouble, the old owner decided to put a nice light weight aluminum water heater in the MH.... problem is it made for a BOAT! the heat exchanger is pumping too much hot water from the mh engine into the water heater and popping the pop off (over pressure) and its getting too hot so its popping the over heat reset too,,, 😞 so now i have to figure out how to cut the heat coming from the mh engine to the tank, i know i can turn off the valve coming from the mh but then i wouldnt have any hot water on the road, thanks

[SkipJ]

You leave it on while you drive? Seems a waste of propane.
SkipJ