Submersible pump wont build pressure, ideas?

[Copymutt]

New 1/2 horse submersible, new pressure tank, new pressure switch.
This is neighbors well, only down 20’ into a 35’ water column.
Old & new pumps run and push water, but will only build pressure to around 47#. Never gets to the cut off of 60#, just keeps running. Shut off the water line at the pump so no feed to the residence makes no difference. 220v on a 20 amp breaker.
Found a lack of ground between supply & pump. Fixed that, no change. Can’t be sucking air as it’s submersible. If the lift pipe had a hole it would bleed down after cutting power. It doesn’t. Don’t have an ammeter so cant see what it’s drawing.
Open to any ideas.

 

[micromind]

If the pump can outrun the well and it draws the static water level down to the pump suction before shutoff, it'll just sit there and do nothing.

If it maxes out on pressure and you come back in 10 minutes and start it again, will it continue to build pressure or does it do nothing.

If it's a new pump, it's possible that it isn't designed properly and the pump part doesn't have enough stages to operate at the desired pressure. In this case, the motor is fine.

In order to properly troubleshoot, you'll need a clamp-on ammeter.

If the amps is close to the nameplate and stays or gradually drops a bit, then very likely the pump is not designed for this application. If it draws close to nameplate amps then drops suddenly, then the pump has outrun the well and is caveating (running but not pumping).

 

[BillK]

What pump is it ?

 

[tarmy]

Look at the head listed for the pump and its’ design. Gotta make sure the set up is suitable for the system.

 

[Copymutt]

Not much head at all, maybe 20’ for a submersible. Old pump was doing exactly the same thing. Yes agree on a clamp on ammeter. Just realized last month they lost power to the residence and retrenched w/ new feed. The line to the well drops from the same service box. Maybe it got knocked and now shorting out a leg
But, Voltage at the control box is 120 on both legs.

 

[PCustoms]

How far is house from well?

Elevation change once outside of the well?

What's the tank like, is there a bladder?

Where are there check valves?

 

[micromind]

Not much head at all, maybe 20’ for a submersible. Old pump was doing exactly the same thing. Yes agree on a clamp on ammeter. Just realized last month they lost power to the residence and retrenched w/ new feed. The line to the well drops from the same service box. Maybe it got knocked and now shorting out a leg
But, Voltage at the control box is 120 on both legs.

Is it 240 from one leg to the other?

 

[Copymutt]

Fixed For whatever reason symptoms same old and new, the new pump was defective. Replaced w/ a Flowtec & all good. Thanks for the replies. Returning defective to HD.
Other concerns. My system is 3/4 galv. from 1957. I keep the running pressure a little low hoping to stave off the inevitable break under a slab. Two zones and I have a visible pressure gauge in the garage to monitor. This has saved my **** when a PVC line broke at the stem wall.

 

[PCustoms]

Fixed For whatever reason symptoms same old and new, the new pump was defective. Replaced w/ a Flowtec & all good. Thanks for the replies. Returning defective to HD.

Everbuilt?

 

[Copymutt]

Everbuilt?

Unsure, I was the third cook in the stew. Don’t think it was Everbuilt.

 

[My Old Tools]

Did it ever build 60psi? Or did you up the pressure switch?

 

[Copymutt]

Original pump and first replacement would never get over 45. Second new pump took off and clocked off at 60. Same pressure switch. What ever seal tech used in the first two failed. Check valves were integral to the pumps.