Concern contractor sabotaged well pump

Old 05-06-24, 06:25 PM
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Concern contractor sabotaged well pump

Perhaps 3-4 times this year during heavy use the water stops running and the pressure goes to zero. After 15-20 seconds the water returns instantly, and the pressure goes back to normal. I had a contractor in to discuss replacing the pressure tank and well switch. He happened to have a tank with him and offered to replace everything on the spot. It was obviously expensive and, given the infrequency, I decided to think it over for a day or so.

He told me the switch could go at any time and showed me the switch didn't manually move the pressure past 40 PSI. (The PSI gauge didn't move.) The thing is the switch is a 40/60 and the pressure was nearly 60 PSI when he arrived and only went down because we ran the water. The pressure has stayed at a high of 40-42 PSI since. Thus, I'm concerned the contractor adjusted the switch to a narrow range in order to encourage me to have work done.

Is there a way for me to check to see if the switch was adjusted?
Old 05-06-24, 06:59 PM
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The pressure switch has an adjustment screw under the cover of the switch. I don't think there is that much adjustment on the screw but you can check yours out to be sure. Setting a 40/60 pressure switch to only 42 psi would cause the switch to turn on and off rapidly.
Old 05-06-24, 10:34 PM
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during heavy use the water stops running and the pressure goes to zero
It is not a defective pressure tank. The system doesn't need a tank to pump water.
Doubtful the switch is bad either.

Sounds morel like a over draw down issue. Lack of water in the shaft.,

This is a submersible well..... correct ?
Do you know when the pump is running ?
Sometimes you can hear it next to the line coming in from the well.
You can hear and see the pressure switch click on and off.

If you can't tell when the pump is running.,.,,, take the cover off the pressure switch and measure the voltage going to the pump. It will be near 0v if the switch is open. It should be 240vac when closed.

There will be two wires coming in and two going out to the pump.
You want to measure the pair going out to the pump.
Old 05-07-24, 05:20 AM
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I had the same symptom, run the water for a while and the pressure would drop off to zero. Wait a few seconds and the pressure would come back and water would flow. I ignored it for a while until it started happening almost every time we used the water. Turns out we had two issues, the first was the pressure tank air bladder was over charged. Can't remember exactly, but I think it was 45psi. Tank should be a couple of psi below the low pressure cut off setting of the switch. Second issue was grit in the line was clogging up the switch or at least messing with it.
Reset the tank pressure to the correct psi and since the switch was very old, replaced it. Everything is working great now.
Old 05-07-24, 06:01 PM
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If the pressure tank is overcharged it will keep the system pressure higher than the pressure switch setting so that the pump won't run.... or run very shortly.

In this case.... the pressure is 0.
That eliminates a pressure tank issue. (at least as to causing no water at all)
Old 05-08-24, 10:23 AM
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In my house whenever I install a new pressure tank or pressure switch, or just want to troubleshoot pressure problems. I take the cover off of the pressure switch, run water continuously, and observe the operation of the switch while watching the pressure gauge. (Assume you have gauge near switch).

You can hear the clicks and you can actually see the relays open close as the switch operates. You will see the system go up to the high pressure and then the switch relays open and turn OFF the pump. As water is continually used the pressure will go down and you will see the relays close at the low pressure and the pump turn ON. And so on and so on.

You just need to run the water continuously at a few gallons a minute.

Inside the cover of the switch there should be a little diagram that tells you which screw to turn to adjust the pressure up and down. It's easy to adjust.

I think you should be able to tell if your switch is misadjusted or just plain broken. Also, if your pressure gauge really doesn't move then it is broken and you will have to install a new gauge to figure out what is going on.


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