Water Pump Runs Continuously

[DnDatGrdJct]

The pump appears to be sucking air from someplace. It will not shut off. It does pump water and all the valves are set correctly. Plenty of water in the holding tank. The hot water line appears to run OK but the cold water line sputters and shows air bubbles at all faucets. Get almost no flow from the kitchen faucet. When checking the lines underneath I can see air bubbles in some of the lines. Talked to the dealer but can not get appointment until May 14th. I have tried to tighten all the fittings and they seem fine. Hoping someone can give me an idea of what might be checked for air leak, if that is what it is or an idea of what other problem may be present.

Thanks for any help.

[Waynem]

Have you checked the connection at the pump?

[rogue]

Are the outside valves set correctly? Hot water valve NOT on bypass, Fresh water NOT on fill tank, and winterize should be off (forget what that says). And outside shower is turned off (both hot and cold water knobs).
Bob

[H. John Kohl]

I had the same problem at the PDI. My problem was the fresh water tank fill valve was in the fill position. So the holding tank was pumping right back into itself. That would be the first place I would look.
Good luck and let us know what you find.

[FLSTS03]

Dean,
Since you have a full tank the pump should be picking up fine and because the lines are tring to purge,pressure is coming from somewhere. Try to lift the T&P valve lever on Water Heater to purge the tank of air.I would bet there is a lot of air in the lines, you did not say hold long you ran the faucets. Steve

[DnDatGrdJct]

Thanks to everyone for your replies.

I have checked that all the valves are in the correct positions. The outside faucets are both turned off. The connection at the pump appears to be tight. The hot water heater had been purged of air. The low point drain valves are closed tight. I had the pump running the entire time I was checking the fittings of all the lines at the control panel and by the pump - that must have taken 10 minutes.

We used the unit for four days last week on city water and everything worked fine. I had filled the fresh water tank about half full from the control panel and then made sure the valve was not in tank fill position. Never tried the pump before we left. Also had used the city water to purge the antifreeze from the system while getting the unit dewinterized.

Not sure if this more complete information will give anyone other ideas I can check. All your help is most appreciated.

Dean

[sgtpp214]

We had similiar problem with pump running periodically when no water had been used. Dealer found some fine pin holes in line from fresh water tank to the pump. Water line replacement cured the problem.

[sreigle]

The only other thing I can think of is a defective diaphragm in the pump. Like a rip in it. That can be fixed with a repair kit in many pumps. Or replace the pump. Do you suppose your dealer would have an old but working pump you could connect to make sure it is the pump before you buy a new one or repair kit?

[MacDR50]

If you have air bubbles in the suction line you are sucking air however this alone shouldn't cause the pump to run continuously. It is pressure on the discharge side that makes the pump cut-out once the set pressure is reached. Most are factory preset. Air in the discharge side will cause a pump to take longer to come up to pressure as the air is compressible but it will finally get there. It will also cause hammering when the pump runs as the air pressure creates a springing effect as the pump diaphragm moves. A weak seal or rip where the diaphragm seals to the pump housing flange will cause the run-on. Basically the pump cannot reach the cut-off pressure due to an internal leak between the discharge and suction side. This would show as air in the discharge if the leak is open to the atmosphere on the suction side. It would be a visible water leak if on the discharge side. This may not be as evident on the hot water system as it has a tank which acts like a water tank on a well system but would cause the sputtering on your cold water side. In summary, I am with Steve Reigle on this one. Check around the housing where the two halves join, if this is your type of pump. Run the pump and wet your finger and slowly run it around the seal while the pump is running. If the pump changes sound this is a good indication where the leak is to be found. If you are lucky, tightening the screws that hold the pump halves together may solve your problem. If not then consider a pump kit. They are available from Shurflo.

Added on edit. From a Shurflo manual:

PUMP WILL NOT SHUT-OFF:
#1048577; Output line closed and no leaks
#1048577; For air trapped in outlet line or pump head
#1048577; For correct voltage to pump
#1048577; Debris in pump Inlet/Outlet valves
#1048577; For loose drive assembly or pump head screws
#1048577; Pressure switch operation/adjustment

[Crossthread]

Have you tried capping off the city water inlet fitting? I had one that had a bad O ring in it,and it would suck air. Bill

[DnDatGrdJct]

Problem Solved.

Many thanks to everyone for your suggestions. This is the greatest group for helping solve problems.

Managed to talk with the service manager of the local dealer and he felt certain there was an air leak in a fitting on the supply side of the pump. His advise was to put the system on city water and again check all the fittings for being tight. He also suggested that they should be just a bit beyond finger tight. When I did this there was one fitting that showed a small water drip. As murphy's law suggests it was way back and nearly impossible to reach. Managed to tighten it and everything now seems to be working fine.

Again thanks to everyone.

Dean

[Waynem]

All's well that ends well.