Experiencing What I Call a "Water Harmonic" - RV-Dreams Community Forum

Terry and Jo · RV-Dreams Family Member

Experiencing What I Call a "Water Harmonic"

GENECOP · RV-Dreams Family Member

One quick way to isolate. If it is a vent problem, it is connected to water going down the drain only, dump water down the drain from a bucket, try to simulate the flow from the faucet. The next thing is to run the Hot water but don't let it go down the drain, divert to a bucket....if all attempts fail to produce said Harmonics, take two aspirins and chalk it up to mental problems.......

Workinrvers · RV-Dreams Family Member

on the back side of the water heater is a check valve that is a common failure and tends to make a humming type noise when it starts to "go".
Ours started humming about 6 months ago so I picked up a new one to have on hand but will probably wait until it fails completly before replacing it.

You will hear the humming, not real loud but noticable, when you are running the hot water. Could this be the noise you are hearing?

Phil

Terry and Jo · RV-Dreams Family Member

Phil,

I've received replies on another forum where the are saying an "upper check valve" is likely the problem. With your description, I'll open the basement doors tomorrow and have Jo turn on the water. If it is from that location, I think it will be narrowed down.

Being that this is a Mobile Suites and presuming that an "upper" check valve might mean a "lower" check valve exists, I may have to do some more looking to find the location for sure.

Thanks for the answer. Now I know where to start looking.

And thanks to Gene as well. I hadn't tried his suggestion yet, but since the washing machine also causes it and drains are in different locations, I think it is likely that the check valve is the culprit.

Terry

Workinrvers · RV-Dreams Family Member

don't think there is a lower check valve on our water heater in our Montana. The valve in question is screwed in-line with the water line at the upper most connection on the back of the water heater.

Good luck,

Phil

Terry and Jo · RV-Dreams Family Member

Yesterday after work, Jo was washing some clothes and while I was outside I heard a short buzz near the hot water heater. So, I went inside and turned on the hot water and went back outside.

The buzzing was definitely in the hot water heater area, but when I touched the check valve at the top of the hot water heater, I couldn't feel it in the check valve. However, it definitely sounded like it was there.

Something to add with check valves. Some research that I did yesterday indicated that there could be as many as 3 or 4 check valves on an RV. In our case, it looks like we have check valves in both the inlet and outlet of the hot water heater. Other locations possible for check valves are at the 12V water pump and at the city water inlet connections.

I was advised elsewhere to be sure and check out the check valve's ends as some have two male connections and some have one of each.

Now to get a check valve and have it at the ready for when the water actually quits running because of the valve. Thanks for the help, Everyone.

Terry

Workinrvers · RV-Dreams Family Member

Terry,

We also have a check valve/back flow preventer on our black tank flush line. They were nice enough to hide it behind a panel in our kitchen pantry! Thank goodness for RV forums because with out the Montana Owners Forum I would have never known about it much less found it!

Phil