Strange noise in water heater....

[SuiteWheels]

We have a loud humming sound that happens everytime we turn on the hot water. Our neighbor could even hear it!! d/h has drained the hot water (twice) thinking there was a build up but that didn't take care of the problem. He replaced the anode tube but still we have that loud sound.
Appreciate any ideas of what could be causing this and how to fix it. :)

[jack_diane_freedom]

Ours does that from time to time and it appears to be the check valve just behind the outlet. Various water pressures seem to make it stop or make noise. Also could be some kind of temporary foreign matter in it. It is amazing what shows up in the water filter.

[rverdlm]

I had the same probem, it's the check valve!

[Huck]

I have the same problem too.

Tried go get a check valve at Camping World. They thought I was nuts. They said to go to a hardware store to get one.
Camping world sure isn't what it used to be. They just don't have the repair parts that they used to carry.

I got one on Ebay last year for my black tank flush.

[Motor31]

I have the humming sound as well, not too loud but it's there. I can't find the check valve on my water heater. All I see is a standard brass "bib" that connects the RV plastic water lines to the water heater.

[rverdlm]

Mike, it's on the top inlet on the back side. It screws right into the water tank. It's only about 1/2 to 3/4 inches long and the plastic pipes attaches to it.

[SuiteWheels]

Thanks so much for the replies. d/h said, oh that makes sense and was glad that reverdlm told where it was located. Now to find where to buy one! :)

[jcasey]

TI discussed the issue of the water heater noise with Double Tree, now DRV.

This is a paraphrase of what I was told, ". . .the noise is coming from a valve on the back of the water heater that we install. If owners call Kent Mickem he will send them a new valve and tell them the location---where to find it."

[WildJohn]

Well I read this after I noticed the same noise. kinda ignored it until we suddenly were without hot water. (it is amazing how you can get ready for work without hot water.) I am thinking the check valve has now failed. I will go look at it and contact DRV in the morning.

[Huck]

Here is a link to the one I got. Works great..
http://cgi.ebay.com/ebaymotors/NEW-Back-Flow-Preventer-for-RV-Camper-Trailer_W0QQcmdZViewItemQQ_trksidZp1638Q2em118Q2el 1247QQcategoryZ50073QQihZ012QQitemZ220268731418QQr dZ1QQsspagenameZWD1V

[Gunship Guy]

I replaced ours last year. I found it easier to go through the access panel in the pantry (38RL3) versus trying to reach it from the basement.

[WildJohn]

Welllllll I checked all around here and only found some 3/4" check valves at the local home improvement stores and figured that by the time I adapted it to 1/2" it would be too long. The local RV dealer only had a plastic model and is 20 miles away.... I took it out to compare and found that the plunger was moving freely from the spring. looks like a retainer is missing... I put it back in without the check valve function functioning and made our shower much more functional until I can get a replacement to function...(DW said the first hot shower in three days felt PRETTY NICE and we won't discuss how long it was) I think part of the decision might have come from doing it at 10 degrees F. with a pretty good wind blowing.
I didn't even know there was an access panel in the pantry where I can reach it. I need to remove a few hundred pounds of staples from the pantry and look for it... can you give me a little more direction as to where it is.. I know where the one is behind the shower at near eye level.
Thanks everyone... this would have been a real head scratcher if it were not for this forum
John

[Gunship Guy]

John,

Mine has an access panel at the very bottom of the pantry held in place by 4 small screws. There's also the one for the shower that you mentioned.

Because the water heater is set back a ways it was just easier and I got better leverage going that route. I just couldn't get the right angle with my wrench going through the basement sliding door.

[WildJohn]

Is it on the wall or floor of the pantry?
if it is on the floor mine doesn't have one (YET) I cleaned it out a couple of weeks ago and the linoleum goes all the way under the cabinet.

[Gunship Guy]

It's on the wall of the pantry below the bottom shelf.

[Motor31]

I just looked in my pantry and saw a small access panel on the far right side at the floor or bottom shelf level. It may be partially blocked on mine by the shelf support, I'll have to look closer later on.

Thanks for the info Guns.

[RonS]

This morning while taking a shower, mine started to sing the song, so went to Lowes who did not have that size back flow preventer. What will happen if I dont replace the valve?? We still must live in the MS until the end of May, and will be for the most part in the travel mode, thus no mailing address.

[WildJohn]

CAN YOU SAY COLD SHOWER... VERY COLD WHERE WE WERE.. temps near 0 F. can do that. Only heat tape keeping it from becoming hard water. LOL
I haven't yet replaced mine after eliminating it, but have had plenty of other projects to keep me busy.
good luck,
John

[RonS]

I found a back pressure valve at a RV Sales place, and replaced the old one. Looked inside and a rubber O-ring was shot. Like all who gave advice on this subject it was an easy fix. Thanks to all, this is a great forum.