Sudden Low Pressure from Submersible Pump

[Liam DuBoise]

Hey everyone,

Sudden well problem: The ability of my submersible well pump to pressurize the system has suddenly dropped from 70+ psi to 30 psi (85-gallon air-over-water tank). It will just go to 30 psi and keep running. This is a 2 hp pump in a 4 inch well of unknown depth. I had to dial down the pressure switch to keep the pump from running constantly. With no water running in the house, the pressure holds at 30 psi with the pump off. Control box is 3 wire CSCR. When the pump turns on, voltage on the 3-wires is 120 , 120, and 320. I checked the pressure 2 days ago and it was 68 psi. I am not a plumber or an electrician, but I am not afraid to tackle any repair project.

Any help or insight would be GREATLY appreciated.

Thank you!

 

[Reach4]

I checked the pressure 2 days ago and it was 68 psi.

You checked the pressure before there was any symptom? And now there is this symptom. What are the odds?

The problem could be a failing pump. If you have an above-ground check valve, the problem could be a hole in the path from the pump to the pressure tank. It is usually best to not have an above-ground check valve.

 

[Sponsor]

 

[Liam DuBoise]

You checked the pressure before there was any symptom? And now there is this symptom. What are the odds?

The problem could be a failing pump. If you have an above-ground check valve, the problem could be a hole in the path from the pump to the pressure tank. It is usually best to not have an above-ground check valve.

Thanks...Yeah; what ARE the odds? I was doing a routine clean out of spiders and lizards from around the pressure switch 2 days ago...
Does that 320 V reading on the 3rd wire sound normal? Also, there is an 85-gallon bladder tank in line with the 85-gallon air-over tank, and the bladder recently failed; I haven't been able to replace it yet. There is no isolation valve to shut off the flow to the bladder tank. All of the piping for the whole system is above-ground and accessible with no leaks evident.

 

[Valveman]

It does sound like you might have a hole in the well pipe before the above ground check valve. Although this usually causes air to blow out the faucets. The bad bladder tank could be absorbing the extra air? 320V is not uncommon on the run capacitor lines. Remove the top check and see if it holds pressure when no water is being used.

 

[Liam DuBoise]

It does sound like you might have a hole in the well pipe before the above ground check valve. Although this usually causes air to blow out the faucets. The bad bladder tank could be absorbing the extra air? 320V is not uncommon on the run capacitor lines. Remove the top check and see if it holds pressure when no water is being used.

Thanks again...
Yes; it looks like a check valve just past the 90-degree elbow at the top of the casing. There’s a way to bypass or remove it? Looks like it might be a bear to remove... galvanized to PVC.

 

[Valveman]

The PVC should come out fairly easily. You can remove the poppet from inside the check valve and put the body only back on just to get the plumbing attached.

 

[Reach4]

You might consider changing the start cap on your CSCR control box some day. That is not causing you a problem, because your pump is starting. The run cap is not an electrolytic, so is not destined to ever fail. If the pump start ever becomes intermittently delayed, get on that cap.

Also, if you take that poppet out, takes some pictures. You may or may not decide to post, but I don't think we have seen photos of that procedure.

 

[Liam DuBoise]

You might consider changing the start cap on your CSCR control box some day. That is not causing you a problem, because your pump is starting. The run cap is not an electrolytic, so is not destined to ever fail. If the pump start ever becomes intermittently delayed, get on that cap.

Also, if you take that poppet out, takes some pictures. You may or may not decide to post, but I don't think we have seen photos of that procedure.

I am now getting air in the lines inside the house; I first thought it was related to the bad bladder tank. I replaced the start cap about 7 years ago...
I am attaching a photo: Does this look like a check valve?

Thanks!

 

[Valveman]

No that is just a union.

 

[Valveman]

(85-gallon air-over-water tank). It will just go to 30 psi and keep running. This is a 2 hp pump in a 4 inch well of unknown depth. I had to dial down the pressure switch to keep the pump from running constantly. With no water running in the house, the pressure holds at 30 psi with the pump off. Control box is 3 wire CSCR. When the pump turns on, voltage on the 3-wires is 120 , 120, and 320. I checked the pressure 2 days ago and it was 68 psi. I am not a plumber or an electrician, but I am not afraid to tackle any repair project.

Any help or insight would be GREATLY appreciated.

Thank you!

30 PSI and air in the lines sounds like you have a hole in the line down the well. The check valve will be before the pressure tank, probably has a Schrader valve and maybe the pressure switch attached to it.

 

[Liam DuBoise]

No that is just a union.

Thank you! Following the flow, I also found an above-ground Wilkins Model 700. It is past the bladder tank and before the air-over-water tank. Is that the one I need to pull to check for a drop pipe hole?

Thanks again!

 

[Valveman]

Past the bladder tank but before the air-over-water tank??? Might need to post a picture or two of your system. Usually have one or the other type tank?

 

[Liam DuBoise]

Hi again,

I cut the pipe to the bad bladder tank and installed a valve there for now. I pulled the Wilkins 700, and it is a double check valve; I could get the ball assembly out from one side only, and there was a lot of crud inside. I put a straight piece of PVC in temporarily and ordered a new check valve. I fired up the pump and the system gets up to 40 psi now instead of 30... can't figure out why that would be. I shut off the power and isolated the system and the pressure held steady at 40 psi all day.

Does that sound good for the drop pipe? Or might there be another check valve down the casing somewhere?

I also figured out one of the mystery pipes just past the bladder tank: I have an irrigation well about 30 feet away from the house well, and they are tied together underground with a 1-inch PVC pipe! I am able to supply water to the house system from the irrigation well. It is a 5-hp pump in a 4-inch casing of unknown depth, but my neighbor seems to remember it being much deeper than the house well. It puts out massive amounts of water, and much better quality than the house well. We used to irrigate 5 acres of orange trees with it before they all died from citrus greening...

Thank you!

 

[Valveman]

I still don't understand your system? But if that is the only extra check valve and you removed it, then the low pressure is probably because your pump is gunked up like everything else. Those double checks have about 10 PSI friction loss, which is why you have 10 PSI more now.

 

[Liam DuBoise]

I still don't understand your system? But if that is the only extra check valve and you removed it, then the low pressure is probably because your pump is gunked up like everything else. Those double checks have about 10 PSI friction loss, which is why you have 10 PSI more now.

That is the only above-ground check valve present. Attached is a flow diagram that I made. a possibility that I only need to pull the pump and clean it? I was wrong about the size of the air-over-water tank; it is 120-gallons.

Thanks again,

 

[Reach4]

Attached is a flow diagram that I made.

1. Is there a drain valve near #4?
2. If you do not use water in the house, and turn off the pump, does the pressure gauge reading hold?

 

[Liam DuBoise]

1. Is there a drain valve near #4?
2. If you do not use water in the house, and turn off the pump, does the pressure gauge reading hold?

1. There WAS no drain valve near #4, but I cut the line and installed a 1-1/4" ball valve so that I could remove the bad bladder tank and replace it.

2. If I do not use any water in the house and turn off the pump, the pressure holds steady at 40 psi for at least 2 hours.

 

[Liam DuBoise]

1. There WAS no drain valve near #4, but I cut the line and installed a 1-1/4" ball valve so that I could remove the bad bladder tank and replace it.

2. If I do not use any water in the house and turn off the pump, the pressure holds steady at 40 psi for at least 2 hours.

Also, I completely drained the air-over-water tank before turning everything back on. It seems like instead of compressing the air in the top of the tank as it fills, that it is just pushing the air out of the top of the tank... ?

 

[Reach4]

1. There WAS no drain valve near #4, but I cut the line and installed a 1-1/4" ball valve so that I could remove the bad bladder tank and replace it.

A drain valve would let you let water and sediment out. It would let you mount a garden hose thread pressure gauge to check your main pressure gauge.

Also, I completely drained the air-over-water tank before turning everything back on. It seems like instead of compressing the air in the top of the tank as it fills, that it is just pushing the air out of the top of the tank... ?

How does the air get introduced? Is that coming in through the well pipe?

Failing pump sounds like a good candidate, unless you have some undiscovered check valve.

 

[Liam DuBoise]

A drain valve would let you let water and sediment out. It would let you mount a garden hose thread pressure gauge to check your main pressure gauge.


How does the air get introduced? Is that coming in through the well pipe?

Failing pump sounds like a good candidate, unless you have some undiscovered check valve.

I completely drained the air-over tank to eliminate saturated air (read that on this forum!). So at this point the tank was totally filled with air... right?Then closed all valves and turned the pump on. The I could her the water going into the tank, and the system came up to 40 psi and the pup cut off. When i turned on the water in the house, I could hear huge amounts of air being pushed into the softener, which ultimately went into the house lines. I think the tank is 100% filled with water now, but I'm not sure.

Does the discharge pipe in the air-over tank go all the way to the bottom of the tank? Might this be broken or dislodged inside the tank?

Is my next step to take the control box off, loosen 4 extremely rusted bolts on the well cap, and try to pull? If so, any tips? I'm praying for a flexible drop pipe...

I do have a professional-grade pressure gauge attached to a hose bibb adapter that I can try, if I can find it.

Thanks again...your help is massively appreciated...