Fresh tank filling up by itself

[Nealp49]

Here's one for you. My fresh tank occasionally fills up by itself when we are camping even though the water valve is set to city water. It will eventually fill and start coming out the overflow. Doesn't do it all the time but just sometime......like today for example. RV dealer looked at it yesterday and couldn't duplicate problem (naturally) so nothing done as of yet to correct. Any ideas? ?

Didn't mention that I have a 2015 Big Country 3450TS with the fresh water tank problem.

 

[jimtoo]

Hi Nealp49,

Sounds like the check valve in the pump is leaking back to the fresh tank or the water valve in the udc is leaking backwards to the tank. You might rotate the udc valve around and try it. Some have gotten some little something in to make the leak or even the orings could be bad.

Jim M

I also combined your post.

 

[Nealp49]

Thanks for the reply. The last time it happened I was able to stop it by rotating the valve in the UDC a few times, but it didn't stop the problem today. One of the techs at the RV dealer also mentioned the Check valve in the water pump. Yesterday the techs said they couldn't duplicate the problem therefore they didn't try to fix it. I thought that was a pretty lame excuse. Today I made a video of it and will take the unit back to the dealer this Monday.

 

[cookie]

You could just add a check valve at the water pump. An inexpensive fix rather than leaving your BC at the dealer.
I the mean time just leave the fresh water tank drain valve open.

Peace
Dave

 

[asherwin]

I had the same gradual filling of the fresh water tank this winter while in Florida. Turned out to be the Anderson valve. Replaced it and no more issue.

 

[Nealp49]

???? What is the Anderson valve? I don't recognize that term. Is it the valve in the UDC that you rotate for city water, fresh fill, and water pump? ? ?

 

[asherwin]

Yes, the Anderson valve is the four way valve in the UDC.

 

[Nealp49]

Thanks again

 

[danemayer]

We have an Anderson Valve Service Manual here. Looks like it would be pretty easy to remove the central rotor and inspect the condition of the seats and o-rings. Maybe save a trip to the dealer. If you find anything interesting, please post pictures.

 

[LuckyLargo]

I have replaced the valve and the pump to no effect. The fresh tank just fills up. Any ideas?

 

[yport]

Now there's a problem dear to my heart. Know your frustrations, because the problem comes and goes. Heartland first thought it was a faulty Anderson Valve ...(UDC) so they sent me a new one to have installed (free). Same problem on and off. So your problem, like mine, is either the UDC ... or the check valve in the water pump, as mentioned here. A quick, cheap fixe for that is to install a Shurflo Inline Check Valve ($12) ... if your hoses to the water pump are the flexible type (like a garden hose is) ... or if you have the PEX tubing like I have .... install this: http://www.homedepot.com/p/SharkBit...o-Connect-Check-Valve-U2008-0000LFA/202721919 which I got at Home Depot ($15). Both are a snap to install and a lot cheaper than buying and installing a new water pump.

The Shark Bite valve I am installing shortly, which should fix my problem .... if that doesn't, then I will know for certain that I somehow ended up with 2 bad Anderson Valves!!

 

[LuckyLargo]

You could just add a check valve at the water pump. An inexpensive fix rather than leaving your BC at the dealer.
I the mean time just leave the fresh water tank drain valve open.

Peace
Dave

Dave, I know this is probably a dumb question, but where do you put the check valve?

 

[cookie]

You can put that check valve in line with the water pump.
I don't think it will matter if you put it ahead or behind the pump in that water line.
Just be sure you have the flow direction of the valve correct.
The link that yport provided, [link], is a good choice and will be installed in the 1/2" PEX line.

Peace
Dave

 

[GWRam]

One thing you may consider if the problem happens only at certain campgrounds is your pressure regulator or lack of one when you connect to the campground water source.

Reason I suggest this may be part of the issue is: we do not have the anderson selector valve, just the old fashion gravity fill port. We have not had any fresh water tank self filling issues. Until.
Before going to Goshen we switch from our 40psi water regulator to a new 50psi regulator.
After first night of camping enroute to Indiana we noticed water in the fresh tank. Emptied and continued to Goshen. While at Goshen over 9days the fresh water filled to 2/3. Emptied and continued on. Next two campgrounds no noticeable change in
fresh water level. This variable pattern continued for a month. I am going to put the 40psi regulator back on for next trips.

Just a thought that the check valves in the water pump and the seals in the anderson valve may be designed for a certain pressure. Above that pressure water gets through. I do not know what pressure my 40psi or 50psi regulator is actually letting
into our water supply hose.

Just a thought

 

[lynndiwagoner]

Check out this thread: //heartlandowners.org/showthread.php/50108-Installing-check-valve?p=398395&highlight=#post398395

everything you want to know.