FAQs on how to restore a well or water pump control switch back to its original or factory settings for CUT-IN, CUT-OUT pressures.

This article series describes how to adjust building water pressure by setting the water pump cut-in and cut-out pressure on the well water pump pressure control switch.

What are the Usual Water Pump and Tank Pressure Control Settings in PSI?

These questions and answers about how to set the pump pressure control switch CUT-IN and CUT-OUT or DIFFERENTIAL pressures were posted originally

at PUMP PRESSURE SWITCH STANDARD (PSI) SETTINGS - be sure to review that article.

Also see our index to all water pump control switch FAQs at WATER PUMP PRESSURE SWITCH REPAIR FAQs

Article Index

• [We're in process of editing the Q&A below - Ed.]

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Pump Pressure Switch Settings are Less than What the Pump Manual Says They Should Be

My pump pressure gauge is reading 40 psi at kick in and shut of at approximately 60 psi.

I took my tire gauge and checked tank. Its reading 27 psi.

The setting required on pump is saying kick in at 30 and off at 50.

What does this discrepancy imply? - thanks for any advice On 2020-11-27 by susan

Solution by (mod) -

Susan
Water-Tank-Bladder-Pressure-Adjustment-FAQs.php
Good going on measuring the pressure tank's pressure.

If you turn the pump OFF and then run water at a nearby tap until it stops, at the pressure tank you should expect to see about 2 psi less than the pump's CUT-IN pressure.

So a spressure witch set to CUT-IN/CUT-OUT of 30/50 psi would mean we set the air pressure pre-charge on the tank - under the conditions I just described - to about 28 psi. 27 psi is OK.

If your pump is to operate at higher pressure range of 40/60. and provided that setting it up to that level doesn't disclose well that runs out of water, the pressure control switch can be adjusted to CUT-IN at 40 and CUT-OUT at 50 psi.

We describe in detail how to do that at PUMP PRESSURE SWITCH STANDARD (PSI) SETTINGS

You'll see that you'll have to increase the empty water tank air pressure to 38 psi. - Daniel F.

Pump switch kicks on/off at pressures different than what we think are our switch settings

My well is not quite a year old, we have always had plenty of water and pressure. we have been watering trees in yard, now for some reson our pup runs out of water

It recovers with in 5 to 10 min . The guage kicks on at 40 ps and should kick off at 60 or so. It kicks on fine but kicks out at 50 , is it the pressure switch? If I hold the switch down manually it pups and kicks out at 60 or 65 - Shaun Aden 8/4/11

Reply:

Shaun the pump might still be actually going off at 60 if the gauge is clogged with debris and reading inaccurately.

Else if no one "adjusted" the switch and it's cutting off early it's time to replace it.

Debris clogging in the pump pressure control sensor port or in the tube that conducts water pressure to that sensor can cause the swith to fail to operate at all or can cause it to fail to respond properly to water pressure changes.

Also see WATER PUMP CONTROL SWITCH DEBRIS CLOGGING FAQs

I'm having trouble getting the right settings on the pressure control switch

I have just replaced all parts between the well pump and the pipe going into the house, reason was I had a leak and a broken check valve so the system was sucking in air and letting the water reside back down into the well.

My issue now is, that I have a cut in at 38 PSI, and should have a 20 PSI delta, however the Presure Switch does not turn off until 66 PSI.

I have adjusted the big nut to get the cut in down to 38, used to be higher, however I am not able to get the pump to turn off at 58 / 60 PSI.

The little nut is released to the point where the spring is almost loose, any suggestions or do I have a "Old" faulty pressure switch and need to replace it?

I have put in new pressure tank and the pump runs approx 3 min from when it kicks in at 38 PSI, to it has put pressure on the systems to 66 PSI, however if we have 2 faucets open at the same time the system struggles to get to 66 PSI - Thomas 9/1/11

Here is a little info I gathered, from what I have read mine system seems like it has some poor adjustments:

I have a Square D 9013FSQ2 Pressure Switch I checked my cut-in which is 58lbs and cut-out at 69 lbs and i put a tire guage on my pressure tank and it read 70 lbs seems a little crazy. I have a submersible pump at a depth of 120'.

I am going to replace the pressure switch since I feel that is my breaker popping problem.

But with these readings I have bad adjustments. it has been like this for almost 11 years now, just dont want future problems. Could someone help me with what all these settings should be and best way to adjust them. I like higher pressure for watering lawn etc. but dont want problems. - David 11/5/11

Repair directions from mod

Thomas I wonder if you carried the adjustment too far. Typically residential switches run 20/40 or 30/50 psi.

Check the labels and instructions that are on your switch to be double sure it works the same way as the models I've described above.

It isn't odd for a pump to run continuously when multiple faucets are open - it's a function of the pump's ability to deliver water (gpm, or pump horsepower) AND the well flow rate.

For a CUT-IN pressure of 38 psi the empty water tank air pressure should be set to 36 psi.

And the CUT-OUT pressure should be 58 psi, though 60 psi is OK. Pushing for higher water pressure than your pump or well can deliver won't work.

Watch out: as your pump "struggles" to get pressure above 66 psi when running two faucets that may be the design limit of the pump: your water flow when multiple faucets are open exceeds the pump's capacity.

A separate limitation on how much water or pressure a pump can deliver can be a well flow rate limiting tailpiece in the well that protects the pump from running "Dry" and being damaged should water in the well fall too low.

 

 

I'd like to get the cut-on at 60 and cut-off at 70.

I just rebuilt a Sta-Rite water pump (JBMG-41S)(2hp). It had never been serviced and had alot of iron build-up. The shaft had seized. After cleaning it out and putting new seals, it was still able to run ok so I reinstalled it.

Then it seemed there was a problem with the pressure switch. I cleaned out the pipes connecting to it and cleaned the switch itself but I wasn't able to get to a setting that wasn't cycling too quickly. I then looked at the air pressure in the pressure tank.

This system is installed in an old 6 floor apartment building. The city supply is about 45psi I wanted to get a cut-on pressure of about 55psi and a cut-off at about 75.

The pressure tank (Challenger pc266r - 85 gallon) turned out to be over-charged.

I'm not sure what the pressure was at but it was over 60psi.

I let out the air until it got to around 51. Now, cut-on pressure was around 55 and the pump was staying on for around 10 minutes before it reached 70psi but even with the differential nut unscrewed all the way I couldn't get the pump to turn off at 75psi.

I finally unscrewed the main nut and the pump went off but now the cut-on pressure was slightly lower.

I'd like to get the cut-on at 60 and cut-off at 70.

Help appreciated. - Ben 4/9/12

Reply by mod: here are the better settings for your tank pressure and pump control

Ben, please take another look at the details in the article PUMP PRESSURE SWITCH STANDARD (PSI) SETTINGS about adjusting the pump pressure control switch.

You'll see that the two adjustments (on switches that have two) do not operate independently, so changing one can require fine tuning the other.

The larger nut shifts the whole cut-in/cut-out pressure range up or down, while the smaller nut changes the width of that range - the differential between cut in and cut out.

Watch out: you should hesitate to try to set the differential - the gap - or the range between CUT-IN and CUT-OUT to too small a number - that can cause pump short cycling.

Set the empty water pressure tank to 48 psi.

Set the CUT-IN pressure to 50 psi.

Set the CUT-OUT pressure to 70 psi.

Watch out: a cut-out pressure over 70 psi risks plumbing leaks, and still higher pressures can burst a pipe or water tank - which can be dangerous.

My pressure control switch only has one adjustment nut

I do see the cut in big spring and nut, but i couldnt find the differential cut off nut, is this indicating that my pump is a very old one? - Old Pump 5/9/12

Reply:

Old Pump: you are describing a different type of pressure control switch that does not give all of the adjustments we describe - the switch may or may not be the same age as the pump itself.

There are indeed some pressure control switches that only have a single nut.

In that case the adjustment nut shifts the pressure switch operating range up and down but the differential - the difference between CUT-IN and CUT-OUT pressure is fixed, typically at 20 psi.

For example you can shift the pump operating from ON at 20 psi and OFF at 40 psi UP to ON at 30 psi and OFF at 50 psi by tightening the adjustment nut.

 

Water pump runs forever if the cut-out pressure is raised above 38

I have a Goulds 1/2 hp J5 deep well pump with a 20 gal pressure tank. I am operating with a differential of 14 psi (20/34 cut-in/out). Due to well limitations, the maximum pressure generated by the pump is 38 psi (pump runs forever if the cut-out pressure is raised above 38).

At this setting, the small nut is completely loosened.

I would like to operate at 24/34, but if I increase the cut-in pressure to 24 (large nut), then the cut-out pressure is also increased, and the pump runs forever (small nut still completely loose).

It seems that I am limited by the Goulds pressure control switch (which is attached to the pump and monitors the pressure by a plastic tube from the pump housing).

Any solution to this? It is a fairly new pump, so simply replacing the Goulds pressure conrol switch does not guarantee a solution, since the specs of the Goulds switch apparently do not allow one to operate with a cut-in/out differential of 10 psi. - Antony 9/14/12

Reply:

Anthony

You're right that the "range nut" (see article above) shifts the whole water pressure cut-in/cut-out range up or down, while the "differential nut" widens or narrows the cut-in to cut-out pressure gap. I SPECULATE that Goulds and other water pump pressure control manufacturers don't allow the range width to be less than 10 psi because you'd find that when running water in the building the pump would be cycling on and off too rapidly.

You'd be better off to set the range so that the cut-in is at 20 psi, and then you can set the cut-out up to 34 psi.

 

Can a wrong pressure switch setting cause short cycling of the pump?

My air bladder tank pressure came pre set at 38psi but the pressure switch is 20/40 is this causing the switch to cycle on off on off?

Second question, there does not seem to be water in the tank,why? i get water from the spigot with pressure and the guage jumps right from 20 to 40 and back again. why? - Patty 9/17/12

Reply: Yes: wrong tank air charge and/or wrong pressure switch settings cause short cycling

Patty,

The pressure in the pressure tank should always be 2 psi below the cut in pressure of the pump.

Check the water pressure gauge when the pump first kicks in before shutting down the pump. IF your pressure tank was really pre-charged to 38 psi, the pump won't turn on until pressure drops to or below 38 psi in the system.

And if your pressure switch is a typical 20/40 switch, it's set to turn the pump on at 20 psi and off at 40 psi.

With a tank pre-charge pressure of 38 psi, theres only a 2 psi operating range before the pump will cut off again - on at 38 psi, off at 40 psi. That would indeed cause "short cycling" of the pump on and off when you're running water

Turn off the pump. Shut the water supply off to the pump, drain the pressure tank by opening the faucet furthest from the pressure tank, then release all the air from the pressure tank.

For a 20/40 switch, pressurize the empty water tank with air to 18 psi - the pump should be turning on at 20 psi.

When you turn the pump back on it will fill the pressure tank and will stop cycling unless you have a leak somewhere or dirty filters. - reply from WaterWorks 9/21/2012 edited by Daniel F for correctness and accuracy.

 

We don't have the money to hire someone - how do we do pump switch adjustment ourselves

Thank for the information on setting the pump pressure switch. We do'nt have the money to hire some one to do this. Our problem is the well itself so how do I fix it myself? - Mike 7/29/12

Reply:

Mike:

Try reviewing the article PUMP PRESSURE SWITCH STANDARD (PSI) SETTINGS where the details of the water pump pressure control switch adjustment are described; if your switch does not match the one described then you just need to know the switch brand and model in order to go to the manufacturer to obtain the exact adjustment instructions.

Watch out: messing with a pump pressure control switch exposes live electrical connections - you can be killed if you touch live wires. Another catastrophe to avoid is setting the pressure too high, causing leaks or worse, a burst water tank that could injure anyone nearby.

Watch out: If by "the problem is the well itself" you mean that the well is out of water or has a very low recovery rate, no pump pressure switch adjustment will fix that.

And unfortunately a low yield well isn't something you can fix yourself, though there are methods that can improve the amount of water you can get out of a well.

See

• WELL YIELD DEFINITION - required well yield & safe well yield
• WELL YIELD IMPROVEMENT - get more water

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Continue reading at PUMP PRESSURE SWITCH STANDARD (PSI) SETTINGS - topic home, or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

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