Water Pump back feeding?

The manufacturer called us. Thinks a faulty check alive in the pump and they will replace it. :)
Thanks everyone!

Yes - it can happen. I replaced my water pump last year and the exact same thing happened. I called the pump company and they replaced it - was a bad check valve in the pump. If the trailer is under warranty you're good.

Ours was doing the same thing, I replaced the check value in the pump, but after a month it started again. I went to Home Depot and added a check value in line and it stopped the problem.

Thank you OldBiscuit.... we did run the full tank through the pump, but haven't tried the city water again.... will see if that did the trick. Gives us a logical place to start :)

YES......even a new rig the water pump check valve can leak back to fresh water tank.

The internal pump check valve (just a flapper assembly) can get debris stuck in it that doesn't allow it to close.
Debris is usually from construction/installation.

Put some water in tank and run pump thru a faucet with aerator removed and flush it out.
IF it still is back flowing you may need to disassemble pump head and clean flappers.
Doubt if it is damaged..just stuff stuck in it.

OR just add an in-line check valve to pump discharge line.


Looks like that Viewfinder has a standard gravity fill on side of rig for fresh water tank.....so no 'mis-valving' just debris stuck in pump check valve from installation of tank.
Flush tank thru drain and then run pump to clear debris from inside pump.
Enjoy.....nice looking rig.

Yep, happened to us last summer. The pump head is bad and this is what happens. Either replace the head(not the motor) or replace the pump and it will not happen. If this is a Shurflo Extreme series, that is a common problem, according to the tech who replaced ours.

Some rigs have a fill valve. In one position it fills the fresh water tank and the other is for city water operation.

We looked in the manual, talked to the dealer on the phone... there isn't a valve or anything that should allow this to happen.

The system should have a check valve on the pump outlet side to prevent that, possibly where the lines join.

Perhaps you have an owner's manual and it tells you where the valve is to control that 'feature.'