water pump

[Brewer & Nancy]

Have just installed a replacement Shurflo water pump due to leakage. Both the old and the new will not shut off automaticly.Where should I start troubleshooting???

Also, water psi entering 09 LTKE is 40psi, water pressure at outlets is 20psi. Where should I start troubleshooting??

Thanks in advance. B

[Troubleshooter]

There are only three things that I can think of that would prevent your pump from shutting off.
1. Defective Pressure Switch in pump.
2. A water leak in the plumbing after the pump.
3. Air in the system after the pump, although over time it should still pressurize and the pump should shut off, or an airlock on the incoming water supply line.

If I were troubleshooting the problem, the first thing I would do would be to verify that the pump is actually pumping water from the on-board water tank.
This eliminates an airlock on the suction side. One way to do this is to disconnect the outlet piping on the pump, and turn it on. I recommend you stand out of the way however, when you do this..
If you have sufficient water flow with this test, then, before reconnecting the pipes, I would try to block the outlet of the pump somehow to see if the pressure switch turns off the pump. If this test is OK, then I would re-connect the piping, and turn on the pump, then open every faucet in the rig until all the trapped air is expelled from the lines, both Hot and Cold water sides. If this is done, and the pump will still not shut off, then I would start looking for a water leak somewhere in the RV.

Now, regarding the pressure problem. I assume you are talking about using external water from a 'city' supply. Where are you measuring the incoming and outgoing pressure? A bit more information might be needed on this problem.

Bill

[KU9L]

If you still have the city water connection going into your rig you will experience this problem. We are parked at my former grandma's house (now called the Circle K Ranch after her estate sale) so I connected our fresh water hose to the house outdoor faucet today. The well water pressure varies 20 - 50 psi depending on how ful the pressure tank is, but the 150 feet of hose in total gave me ~20 - 40 psi at best at our rig's fresh water inlet connection. It took about 25 minutes to fill our fresh water tank with 64 gallons. About half way into the fill I turned the water pump on, it pressurized the faucets but the pump would not turn off as I think the pump was starving to share half of the incoming water with the water inlet. Once I disconnected the fresh water supply the water pump acted normally. I am still scratching my head, but the differential pressure from the pressurized well water confused the pump since it was connected to both the inlet and output side. This might not be your problem, but it sure did happen to me today, LOL.

Thanks,

Dave