Water pump problem

[Bionic_Man]

I installed a new water pump end of last year. It was very similar in GPM to the one it replaced (bigger than the original pump).

I went with this one from Amazon..
Shurflo 5059-1310-D011 5.3 GPM Automatic Demand 12VDC Diaphragm Pump with 60 PSI Built-In Pressure Switch, Viton valves, Self-Priming & 1/2" NPTF Port

We have only been out once since install (and I didn't test when installed in November), but the pump does a short cycle several times per minute. The other issue is that when the pump cycles, it causes the lights in the trailer to dim (doesn't matter if I have electric or just running on 12 volt). Finally, the water pipes seem to vibrate when it pumps as well.

Thoughts on why it is doing this? Bad pump? Bad install? Too much pump?

The trailer has 2 12 volt deep cycle batteries. There is no water leak. I can leave the pump on for days at a time, sitting in my garage with concrete floor, and I never have any water under it.

[DancinCampers]

Air in the lines could also allow the pump to burp. I would start with the outdoor shower and work back to the pump ensuring the air is gone.

Also, make sure the shower and outdoor shower valves are closed.

[rrupert]

I agree you need to adjust the head pressure switch. On the end opposite of the motor, there is a recessed screw next to where the wires connect that requires a small hex wrench to adjust. Turn it slightly one way or another until the pump stops cycling.

[ppine]

thanks Matt.

[dougrainer]

I would adjust the Pump head pressure switch. It may just be that the switch is slightly off. Doug

PS, MOST RV water pumps are 40 to 45 PSI. Yours is a 60 PSI pump.

[Bionic_Man]

Thanks for the early responses. The pump did not freeze over the winer. The trailer is stored in a heated garage that never gets below 45*.

[Matt_Colie]

Bion,

You have two very separate issues.

The lights flash with the pump load means that there is a bad connection. It is probably between the house bank and the panel if all the lights are affected.

The short cycling means that there is a leak. That leak can be anywhere. If you are not finding a drip or a puddle, then it is internal either to the pump (Just because it is new does not mean it is good) or, if you have a valve that allows you to fill the potable tank when connected to city water that can easily be it. Check to see if that valve is solidly closed, If it is a 1/4 turn ball valve and was not cleared correctly, it may have had water left in it that froze and cracked part of it.

Matt

[C_Schomer]

Did water freeze in it over the winter? Id take it apart and check for cracks or if there's any cr@p trapped in any of the valve seats. Each valve works like a check valve and leaking will let water leak from the discharge side back to the inlet side, making the pump short cycle trying to keep pressure on the discharge side. I haven't had one apart for 20 years but they are very simple and the one I took apart did not have any gaskets to worry about replacing... Everything was reusable rubber. I put an inline strainer bowl on the inlet of my pump to catch anything.
That's a heck of a pump and I wonder what the currant draw is, causing the light dimming. All of my sure flow pumps had a screw in the center of the switch cover and I set mine to about 45 psi cut out. IIRC, turn the screw CCW to lower the psi. That might lower your currant draw a little. Craig