Water tanks filling by themselves

deverall11 · Guru

Water tanks filling by themselves

DMaxer · Guru

It might be a job for a priest.

jules47 · The Happy Helper

My first thought was maybe you have left the pump on?

graeme c · Senior Member

Had the same problem with our Avan frances, under warranty the 12v pump was replaced due to a faulty 1 way valve, this solved the problem

Graeme

deverall11 · Guru

jules47 wrote:
My first thought was maybe you have left the pump on?

Why would I use the pump when connected to mains?

Thanks for the thought

Geeco · Senior Member

Generally the water connection on the side of your van is plumbed into the system down stream from the pump. This is done to keep the tank water separate from the hose supply. Then you can have good drinking water in the tank and other water from the local supply separated. On the down stream side of the onboard pump there is a non return valve if that is not functioning correctly water will flow into you tank. That is most likely where your problem is located.
Cheers,

leestevo · Senior Member

We had the same problem with our new Jayco Silverline van...water was filling the tanks by itself. We took it to Jayco, they could not see the problem. So my husband inserted a one way directional valve after the pump and that fixed the problem. No more mains water filling the tanks now.

Dav4Cris · Senior Member

Yep sounds like the one way valve needs cleaning or replacing. Usually a metal valve in the line can be a plastic one. Some van don't have them and it's the pump that stops the water.

OutbackMK · Senior Member

There should be a valve (on my jayco it is next to the water pump) mine is adjustable diaphragm type it stops the water flowing back though the lines that feed the pump when using mains water pressure.
Eventually mine was overflowing out the breather vent above the tank filling points and flooding the area around the van, tighten the valve down a bit and no problems.

JohnR · Senior Member

We had similar issues with our 2013 Jayco Outback Sterling. As with Jayco's policy they replaced the pump which corrected the problem. In recent times we have had (when pump on) water flowing out the intake valve. Jayco advised that a non-return valve should be inserted between the intake valve and the pump. Again this issue corrected. The non return valves's are products of John Guest and cost about $20-. You can fit it yourself or have caravan repairer do the task for you.

JohnR

PeterD · Guru

First of all, go to this page. Scroll down to the bottom figure. This will give you an idea of how your plumbing should be (except perhaps for the in line taps in the tanks.) You will see a couple of non-return valves above the pump. Some manufacturers do not install one of those after the pump. That means that the pump will be operating as the non-return valve. If so it can receive higher pressure from the mains water supply than from normal pump operation. This will bugger the pump and water flow back to the tanks.

If that non-return valve is missing then get someone to install one for you.

Rocco · Newbie

We had this problem with a Jayco Silverline .There is a nonreturn valve in the line from the tap inlet which prevents water going into the tanks from the hose inlet (quality Chinese equipment) get a john guest non return valve and fit between the hose inlet and line to the tanks. About $25 and 10 minutes

PeterD · Guru

Rocco wrote:
We had this problem with a Jayco Silverline .There is a nonreturn valve in the line from the tap inlet which prevents water going into the tanks from the hose inlet

Actually that non-return valve prevents the pump from pumping tank water out the town water inlet.