Pump cycling, no leaks. Am I troubleshooting correctly?

[EcoBuckeye]

I've been doing some driveway testing after bringing the camper out of storage. My fresh water pump is cycling every 6 minutes or so for one second. I have found no leaks anywhere, including on the ground. I've got paper towels jammed everywhere possible and none of them turn damp. The only place I haven't been able to check would be under / behind the shower or under the toilet flush pedal.

I then connected to city water with a digital volume meter attached and I don't see any measurable changes over an hour, measure to the tenth of a gallon. So I think the system is tight. Still no visible leaks in any of the usual places or on the ground.

So since I don't find water and the city water isn't measurably flowing after being pressurized, does this lead me to a possible check valve issue between the pump and the fresh water tank? Something else causing a loss of pressure? The pump itself is installed in a very difficult-to-access location so I don't want to mess with it if that's not a likely culprit.

[mpouls1]

Bad check valve? Maybe the water is flowing back into fresh water tank.

[EcoBuckeye]

Originally Posted by mpouls1

Bad check valve? Maybe the water is flowing back into fresh water tank.

My thought too - can I diagnose this without replacing it?

[mpouls1]

You can try resetting it. Make sure CW is off/disconnected. Run the pump and run some water and then turn off. Then turn on CW again. See if you have water filling up FW tank slowly.

Or you could try taking the pump apart. I've seen some YouTube videos that show how to replace that seem pretty straight forward.

There are directions somewhere in the forum on how to reset the check valve but don't remember where. My directions may not match exactly...HTH

[NMWildcat]

Sounds like either the pump check valve, loose fitting, or air in the lines.
My pump acts screwy if I don't bleed all the air out of the entire system. Think every faucet, outside shower, low point drains.

[KKonyha]

Mine did that and it was a small piece of dirt in the inlet spring/screen for the city water. Stand to the side and depress it after pump has shut off. Will squirt some water out. Did this a couple of times, no more cycling.

[lwbfl]

Originally Posted by NMWildcat

Sounds like either the pump check valve, loose fitting, or air in the lines.
My pump acts screwy if I don't bleed all the air out of the entire system. Think every faucet, outside shower, low point drains.

+1 for air in the lines / hot water tank.

[DustyRoads]

Make sure bypass valves are in correct position. Also check outdoor shower valves and lowpoint drains are capped or shutoff.