Ned help with another well/pump

[Qapla]

This is an irrigation well. It is a 4" well that has a 5HP submersible 3-wire pump with the controller located above ground. It has a "Well-Xtrol" bladder tank. It has 2" drop pipe feeding a 2 1/2" mainline. There is a 2" in-line filter between the well and where the tank is located. It had been working just fine producing about 35 GPM.

A couple years ago, before I was dealing with this particular system, they had a well company say the well needed to be deeper and I was told they drove the casing deeper and added drop pipe but I cannot verify this. The pump is currently at 63' according to the information they recorded inside the cover of the control box.

The system is having problems.

When I remove the bottom portion of the filter and the filter insert and turn the pump on I get full flow. After about 15-30 seconds the flow drops considerably. If left running the flow will begin to surge between full flow and the diminished flow. If I turn the pump off and back on, the flow will be full at first then the surging will resume.

Does this sound like a problem with the pump, controller, tank or the well itself?

I need to let the owner know if he may need a new well or if this one can be fixed.

 

[MillWeld]

A 2" filter sounds awfully small for a system that produces 35 gpm and would get clogged very quickly. Can you show a pic? Are you sure it is not a checkvalve?

Bob

 

[Qapla]

The inlet/outlet of the filter housing is 2" pipe thread. It is the same filter that is installed on another irrigation system at another location that also has a 5HP 4" setup and that one works just fine. If there is a check valve between the pump and the filter it is down the well. With the filter cartridge removed and the filter left open with the bottom removed (thought I said that) the water should gush out of the 4" opening of the filter housing. It does start that way, but unlike it's counterpart at the other location, this one does not keep the full flow.

 

[Egon]

check the water level in the well.

 

[Just Bill]

I am not a well expert by any means but it sounds like you are running out of water.
Either the water level has fallen, the well has filled in with sand, or something along those lines. Its also possible that the casing collapsed.
Seems you are not getting enough water into the well bore to satisfy the pump.
I would run a rope down the well to see if you still have the right depth.
You might need to use a large air compressor and jet the well to clean it out.
Good luck

 

[MillWeld]

Could the pump be cycling on and off be the cause of irratic flow? If so, is the pressure switch defective?

 

[Stimw]

You are pumping more water than the well can recover with the pump at it's current depth. The pump is running out of water, then the level recovers and you get the surge.
Do you know the total depth of the well? You might have to lower the pump if you have room.
If you got the rain from that storm we just had (over 20" here in St Johns Co.) it might start working again.

 

[Qapla]

It is quite possible that the well is running dry. That was what was thought by a well company a while back, but never really determined for sure.

I cannot drop anything down the well with the drop pipe and pump in place and have no way of pulling it out to check. The owner of the apartment complex wanted me to check after the rain we had ... so far we have had 28+" since January - we only had 23" all last year. Before the owner puts in a new well he wanted me to re-check the existing well to see if the rainfall might have cured the problem.

It may be that I will have to tell him that the new well still needs to be drilled.

 

[E/S]

Sounds like the pump is pulling more water than the well can produce.

E/S

 

[MillWeld]

I think you got intelligent answers fro Stim and E/S.