New pump works, but won't stop working

[Globie64]

Okay, so I replaced the old piston and flywheel pump with a new Shurflo. Works like a champ, but doesn't shut off. I think it's filling the hot water heater tank? I'm not using that yet, needs to be replaced. Water isn't squirting out anywhere, just want to make sure it's working properly.

[TG Twinkie]

Is it actually pumping water? If it is, it has to be going somewhere. Open a faucet and make sure water is coming out with a steady flow.
Do you know what the specs are on the new pump? How many gallons per minute at what pressure?
If there are no leaks and you are actually pumping water, there could be a problem with the pressure switch which should be part of the pump assembly.

[dwightdi]

If the pump has primed itself and is pumping water and does not shut off, the cut off switch must not be working, or you have improperly wired the pump. The cut off switch should be in series with the pump and the power from the battery. It may be the pump has no water to pump because it is not primed.

[Jammer]

It will take 2-3 minutes to fill the water heater if it is empty.

[Lumatic]

I think Sureflos have an internal pressure shut off not hooked to an externnal switch.

You can remove the plumbing on the output end to check it is pumping water and cap it to make sure it is shutting off OK.

[Globie64]

I thought it might be filling the hot water heater. It's primed fine and works great, but I wondered if it's filling up all the plumbing and taking a while to displace the air in the lines. I'm so stoked it works

[Globie64]

Okay, so replaced the water heater, fixed the leaking valves, replaced the check valve: the pump works but labors when the faucet is off. I've tried the wires both ways on the switch... any ideas?

[TG Twinkie]

When you say it labors. Is it not shutting off? If all of the faucets and drains are closed. The pump should run until the pressure switch is satisfied, then shut off.
If it continues to run, you have a leak or bad check valve in the pump. It may be sucking air on the supply side of the pump. Check the city water connection to make sure you aren't leaking there.
How old is the pump?
The red wire on the pump is +12 volts the black is -12 volts or common/ground.

[Globie64]

It's brand new. It pumps water just fine, new tank and all new plumbing. No leaks. It runs smoothly when the tap is open and the water flowing, but when you shut the tap, it continues to run and sounds like it's working against the pressure it is building in the lines. Probably a bad shut off in the pump. I reversed the leads...

I wonder if something else is backwards, I switched the two hot wires (motor to switch and switch to hot lug on the trailer) and no difference. I wonder if the something else is mis connected? It's a year old but only now am I running it, having solved some leaks and replaced the old hot water heater.

[ROBERT CROSS]

slow....click-clock-click-clock usually=slo-leak, at least it did for us.

Bob

[Globie64]

no, it's like this: it runs normally when the tap is open, and keeps running continuously when the tap is closed, but against the pressure in the pipes. It's a small trailer, the water manifold is totally visible. All faucets are new, composting toilet so no water there. Something in the pump is at fault.

[CA_Tallguy]

Originally Posted by Globie64

no, it's like this: it runs normally when the tap is open, and keeps running continuously when the tap is closed, but against the pressure in the pipes. It's a small trailer, the water manifold is totally visible. All faucets are new, composting toilet so no water there. Something in the pump is at fault.

But does it eventually stop after a minute or two or less? You mentioned in an earlier post about it sounding like it is filling the water heater and that is certainly normal if it needs filling. It's not clear to me from what you've posted if it eventually stops. Yes, it will run and build pressure when faucets are off until it reaches the right pressure.

[idroba]

Especially on an old trailer, the wiring to the pump may be long and tired, that is the connections, ground lines, fuses, etc. As the pump builds up pressure after all the faucets are closed, it will "labor" and take a bit to come up to the cut off pressure of the pressure switch. On my '74 Argosy the ground line (-) was attached to the metal interior shell of the rig (as built at the factory). When my battery got low as in boondocking, the pump would slow way down and "grunt" after I turned the faucet off. I essentially solved the issue by running a separate ground line from the battery to the pump.

Measure the voltage at the pump as it is going through it's cycle. If it drops below about 11 volts at any time, you need to look at your wiring system, pump switch, battery condition and so on.

[shivtik]

I believe what you are experiencing is the pressure switch located internally to the pump needs adjustment, On the pump body of the unit you will notice a stainless screw mounted at the center of the pump body axis. Counter clockwise turns i.e screwing to the left will increase the pressure ( pump continues to run ) screwing clockwise will lower the pressure ( pump will shutoff at a lower pressure head ) Worked for me when I replaced mine last year, directions should be in the box?

[Globie64]

Hi, no it doesn't stop, and the laboring doesn't sound good. I'll look for the adjustment screw, that seems like the best place to start. I replaced the pump last year, then had the Univolt replaced with a new gizmo and got a brand new AGM battery and some wiring was corrected. It was hooked to shore power anyway. I had filled the water heater through the city water inlet, then filled the tank. I think I've covered all the variables people have mentioned. It really is laboring against pressure, so I think the switch is the place to start. If not that, then I can fiddle with the grounding. Fortunately, it's an older one and the wiring is simple. Maybe it's also just a weak ground, a loose connection to ground?