City Water Fills Fresh Tank

JeffroNC

On my 2019 TAB400 There must be a check valve between the city water plumbing and the fresh water tank. Mine is leaking slowly. When I am connected to city water, my fresh tank level goes up. Any ideas or a photo?

pthomas745

This thread has a discussion about a "sticky" check valve.

https://tab-rv.vanillacommunity.com/discussion/12636/check-intake-valve-for-city-water-sticking

That thread has this thread inside it, which breaks down the entire pump!  And gives some help for a stuck valve.

https://tab-rv.vanillacommunity.com/discussion/6454/fresh-water-tank-mysteriously-filling-when-connected-to-city-water

pthomas745

And, one more about the check valve.

https://tab-rv.vanillacommunity.com/discussion/2756/no-water-help

ScottG

I believe the water pump itself prevents city water from flowing into the fresh tank--either by an internal check valve, or just by the nature of the pump's mechanics.

Per pthomas745's second link above, it looks like it might be repairable.

Tampakayaker

Mine was doing the same thing on a 320.  It was missing the strainer and dirt got into the pump.  I pulled the pump out and disassembled it.  Was just a few screws.  Pulled bits of plastic? out of the diaphragm.  Put it back together and no more backflow.  And I bought a strainer assembly

JeffroNC

Thanks folks. Last night I discovered that it is leaking in both directions. The pump runs periodically when city water is disconnected. I’ll take it apart tomorrow.