Fresh tank overflow

[BillinTexas]

Set to city water feed but is filling my fresh water tank. I only had 10 gallons for travel but now full causing overflow. Remedies? Limited WiFi in campground. Thanks.

[JBill9694]

It pretty much has to be a valve setting issue. Double, triple, (quadruple) check the valves by physically touching and turning the handles to make sure they're turned all the way to their stops (BTDT). This will also help determine if there is a sticky valve or one that is broken, which would then dictate the next course of action.

[Cate&Rob]

BillinTexas
Hi Bill,

Assuming that you have not recently changed any valve setting which might have caused this . . .

My guess is a failed check valve in the onboard pump. This valve keeps the output (pressurized) side of the pump from flowing back to the intake (tank) side of the pump. On City water, the system is pressurized by the campground water pressure, but if the pump check valve cannot block this pressure, water will flow backwards through the pump to the tank.

Rob

[Yoda]

Set to city water feed but is filling my fresh water tank. I only had 10 gallons for travel but now full causing overflow. Remedies? Limited WiFi in campground. Thanks.

Also do not change any valve setting with pressure on the system. Valves can be damaged (O-rings) which can result in the same situation. I agree double check you nautilus settings.

[TedS]

What oring damage? I don't think these valve have sealing features the pass over orings. The are shaft sealing orings, but they are only subject to rotation and tolerate pressure changes as the valves are operated. I have never seen these valves with sheared orings from being operated under pressure. They are simple ball valves or cylindrical valves that seal by fit and not soft seats.

[TedS]

Any check valve on the pump outlet is like wearing suspenders and a belt. There are check valves within the pumping chamber. That is what makes the pump work by preventing backflow, allowing one direction flow.

[Country Campers]

The OP has a Transcend that does not have the nautilus panel with 4 or 5 valves, only 1 valve on the panel. This valve may be the issue but I agree with Rob that the check valve at the pump is probably faulty. I would think if you have a spare check valve for the water heater you may be able to put it in line to the pump just to get by.

Brian

[BillinTexas]

Should closing the valve at pump stop the fresh water from back flowing?

[Country Campers]

Should closing the valve at pump stop the fresh water from back flowing?

It is possible that the winterizing valve could be closed to help your problem but I am not sure.

Brian

[BillinTexas]

I can hear a definite change when switching from city to fresh wwater in the control center so I don't believe it is that valve. I lowered the pressure on the regulator slightly and turned the water back on. Are the valves on the water pump readily available should I need to replace it?

[ncitro]

I can hear a definite change when switching from city to fresh wwater in the control center so I don't believe it is that valve. I lowered the pressure on the regulator slightly and turned the water back on. Are the valves on the water pump readily available should I need to replace it?

I think its built into the pump, but you could get a PEX one and just put it in the line yourself. If your pump line is PEX this should pop right on. If its vinyl tubing well, thats a whole other rabbit hole....

https://www.homedepot.com/p/SharkBit...0LFA/202721919

[BillinTexas]

I think its built into the pump, but you could get a PEX one and just put it in the line yourself. If your pump line is PEX this should pop right on. If its vinyl tubing well, thats a whole other rabbit hole....

https://www.homedepot.com/p/SharkBit...0LFA/202721919

OK, I didn't know what I was looking at. Vinyl tubing is what is there. I'll look at it it closer later. Thanks.

[ncitro]

You will not be able to see the check valve if it is internal to the pump, but an external should work. If its vinyl you can try the shark bite fitting, I think they might be approved for that but not sure. Be warned as you start to move the vinyl tubing around its prone to make the fittings start to leak.