High Pitch noise from Hot Water Heater

[jermanx]

I have a new 2023 Montana 3761FL. Recently, I started noticing a high-pitched noise coming from the area of the Hot Water Heater. The noise starts anytime a hot water tap is opened in the camper, and stops when it is closed. It almost sounds like an warning or fault tone... does the Suburban SW16DELC have something like that? I have it set for electric and the noise occurs whether its turned on or off... any ideas?

[Foldbak]

First off welcome to the MOC.



As for the noise, it must be from the plumbing. It could be virtually any connection. If it sound like it's coming from the water heater, I'd start by checking the valves in the wet bay to make sure their in the correct position. If all is good there remove the panel in the pass through and try to locate the source of the noise. Others will chime in.

[jermanx]

Thanks for the welcome and the advice!!

[Daryles]

I just changed the element in our water heater and now it squeals a high pitch noise when you turn it on.
Normal.

[RMcNeal]

Agree with Daryles. I have had mine give a type of whistling noise from time to time.
Same with the sticks and bricks, but I have to be in the garage near the water heater to hear that one.

[jermanx]

Several have suggested it may be a plumbing issue which I understand, however the sound does not seem like a plumbing issue to me... I have attached a zip containing a video w/sound...

[randerson1]

Originally Posted by Foldbak

First off welcome to the MOC.



As for the noise, it must be from the plumbing. It could be virtually any connection. If it sound like it's coming from the water heater, I'd start by checking the valves in the wet bay to make sure their in the correct position. If all is good there remove the panel in the pass through and try to locate the source of the noise. Others will chime in.

Ours is an older rig, but we had a similar noise after replacing the anode. Since it started after the new anode went in, it was easy to pin point the possible issue. We still had the old anode in the trash and when I pulled it to compare the two, The new one was about 2 inches longer and I gave it no thought thinking the old one had been eaten away. When I mentioned it to an older gentleman in the site next to me, he said the longer anode will fit, but will restrict the water flow and in our case cause a noise. I ordered the following from Amazon per his recommendation and our noise went away along with the hot water coming out in a stronger flow.
* Anode:*Aluminum Anode,3/4” x 5/8” (.75”) x 9.5”L (Suburban/Mor-Flo water heaters)
I’m not sure if this will help your situation, but since he pointed out our older rig had a Suburban/Mor-Flo water heater and this is the size we should be using.
Best of luck tracking down the issue!

[MuddyPaws]

Another thing I would look at would be the anti-backflow valve on the output side, then the input side. There may be more of them depending on your WH make & model.

They're cheap and not too hard to replace if you can get access to them. Almost any hardware store will probably have them.

Be careful about which way the flow arrow is pointing. Get either one wrong and you will have no hot water at all.

I had to replace an Atwood mixing valve. It required removing the entire unit. I replaced all the back-flow valves.

[rohrmann]

I'm pretty sure the sound is actually the water rapidly boiling on the surface of the electric element. No one is reporting the sound when the water heater is in the gas mode. I've had occasion to hear the sound from our water heater and it is definitely the water being heated by the electric element.

[jimcol]

I had a similar experience years back. It ended up being debris in the check valve on the output side of the heater. It wasn't hard to get to from the basement but it was a bear to break loose for removal. Used a 16" cheater bar to finally get it loose.

[jermanx]

Thanks for the input everyone... I have a tech coming to help with this... I will post update after.

[jermanx]

Just wanted to let everyone know.... it was in fact the check valve on the output side (HOT) of the HWH. It was seized up and near shut... surprised we were still getting any hot water... cheap fix! Thanks to everyone that posted.