I have a 2004 Holiday Rambler Presidential 5 th wheel rv. It has a six gallon propane/electric water heater. We just opened camp for the season and we noticed a humming sound (like a small motor running hum) when the unit was heating the water. It was not a running water sound and it stopped whenever I turned the heater off or it turned off itself when the water was hot. I had it on the electric option. By the way, the water got hot as normal. The humming sound was not loud and seemed to be coming from the back of the heater.I called Atwood and they said that was highly unusual. They said it could be the heating element or the relay. But they were surprised by my problem.Has anyone had a similar problem?Access to the back of the heater is difficult. There is a small access square cutout in that black corrugated material that HR used to partition off the water heater.Any help is appreciated. Thank you.

Just thinking...have you flushed out the heater tank recently? If not, it might be full of 'crud.'

Only thing that hums in mine is the water pump. IDK.

Have a 10 gal in a new HitchHiker that does that also, sounds like a sizzling sound when it is heating, figured it was normal, works fine.On edit, just remembered mine is a suburban, not atwood, still does the same thing.

I had the same problem last summer. While having a shower I could hear the noise above the water flow and wondered what the hey that noise was. I discovered it was coming from the heater. When turned off the noise went away. I emptied the heater and refilled making sure that I opened the pressure relief valve to empty out the air in the tank. It didn't make the noise after that. The only thing was that we had been on the road for almost 2 months at that time, using campground electric, so I cannot figure out why it happened. Just brought my rig home yesterday, filled up with water and have the heater on electric. When I get outside I will be checking further. By the way I did get on line and googled my problem at the time and it was recommended to drain the tank, refill and make sure all the air was purged from the tank. Good luck

I completely flushed the tank last fall during winterization.You cannot hear the buzzing sound either in the RV or with all the access doors shut. You can only hear the buzzing coming from the back of teh water heater tank when you are very near the RV and with the access doors open.We have never heard this buzzing in all our years with this RV.

Atwood water heater humming noise | Good Sam Community

13 Replies

jsum
Explorer
Dec 22, 2017
Sounds like check valve.......
dufresne
Explorer
Dec 20, 2017
mine to but it sounds more like sucking air
Farmer_David
Explorer
May 07, 2013
It is the electric element, it gets built up mineral deposits, (white crude) take it out and either clean it good or replace it. While it is out you just as well replace it.
htowners
Explorer
May 07, 2013
Relay's can hum if the control side has low voltage, or possible if there is build up on the contactors from the arc when they close and open.

Also the reason it hums is......... It doesn't know the word's ;)
Add drum rim shot...
jimw606
Explorer
May 07, 2013
I had a check valve that would buzz, but only when hot water was on and running.
bbeezzz
Explorer
May 07, 2013
I removed the electric element on our hot water tank and removed the mineral build up on it. Solved the problem. I always keep a spare electric element just in case it fries.
FLY_4_FUN
Explorer
May 07, 2013
Mine also has a humming/buzzing sound when there has been lots of hot water use. It stops after a few minutes so im assuming its as the water comes up to temp. It not really loud, and I don't worry about it at all. Our rig has been in service four years

Daryll
Camps_with_Crit
Explorer
May 07, 2013
Mine makes a humming sound when on electric function until temp is reached and element goes into rest mode. Always has and my previous trailer too. Never a problem with either.
WallynDiane
Explorer
May 06, 2013
I completely flushed the tank last fall during winterization.

You cannot hear the buzzing sound either in the RV or with all the access doors shut. You can only hear the buzzing coming from the back of teh water heater tank when you are very near the RV and with the access doors open.

We have never heard this buzzing in all our years with this RV.
Pipeman
Explorer
May 04, 2013
I had the same problem last summer. While having a shower I could hear the noise above the water flow and wondered what the hey that noise was. I discovered it was coming from the heater. When turned off the noise went away. I emptied the heater and refilled making sure that I opened the pressure relief valve to empty out the air in the tank. It didn't make the noise after that. The only thing was that we had been on the road for almost 2 months at that time, using campground electric, so I cannot figure out why it happened. Just brought my rig home yesterday, filled up with water and have the heater on electric. When I get outside I will be checking further. By the way I did get on line and googled my problem at the time and it was recommended to drain the tank, refill and make sure all the air was purged from the tank. Good luck