Photograph of Photograph of a water pump pressure control switch with the cover off FAQs: How to Adjust the Water Pump Pressure Control Switch
Q&A on water pump cut-in & cut-out pressures #1

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Pump pressure control switch FAQs:

This article series answers commonly-asked questions about  how to adjust a well pump or water pump pressure control switch.

We provide pump pressure setting advice, procedures & questions & answers about adjusting the pump switch.

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FAQs on how to set the water pump pressure switch cut-in and cut-out pressures

Photograph of Photograph of a water pump pressure control switch adjustment instructions

Watch out: SAFETY WARNING OF FATAL SHOCK HAZARD: if you remove the cover of the pump pressure control switch you can get access to the two nuts that adjust the operating pressures of the water pump.

But watch out! There are also live electrical contacts exposed in this area. If you touch them, especially being near water piping, there is a serious risk of death by electrocution.

Watch what you touch, or have a professional plumber or electrician do this job for you.

The individual well pump control switch repair article links below explain exactly how to set the water pump pressure switch, where the adjustments are located (the large and small nut found under the switch cover), which way to turn the nuts to increase or decrease the pump cut-in and cut-out pressures, and other pressure switch troubleshooting and repair procedures

[Click to enlarge any image]

These questions were posted originally at WATER PUMP PRESSURE CONTROL ADJUSTMENT - be sure to see that article if you need to adjust the settings on your pressure control switch for your water pump or well pump.

Just below is an index into some common pump control switch FAQs that appear in this Q&A series

Recently-asked questions about adjusting the well pump pressure switch

On 2017-03-15 by(Mod) - water runs then stops then returns

Matt, see WATER PUMP INTERMITTENT CYCLING - separate article

On 2017-03-15 21:31:33.763498 by Matt

Water runs for so long and stops then 15 minutes later comes back on. How do I fix this.

On 2016-09-03 by (Mod) - water pump won't cut off on its own


On 2016-09-03 10:36:54.512438 by Anonymous

i have good water pressure but my pump wont cut off on its own

On 2016-08-31 14:25:14.961084 by Mike

We have a deep well at our cottage. One day we had no water. Our plumber came and replaced the pump control box, pressurized the system and said all was good.

That night we had no water. Our plumber came back the next day and found out the control switch needed an adjustment (took 10 minutes) and once completed everything is working fine. The problem is we are in a remote area so a service call costs 4 hours labor.

Our plumber billed us for 2 calls. Wouldn't it be common practice, after installing a new control box, to check that the pump switch was working and adjusted? That would have totally avoided the need for a second service call.

On 2016-07-29 20:58:40.391656 by (mod) - things to check about pumps and water pressure before you call the plumber

Ray, certainly there are things you can check before calling your plumber.

A nice diagnostic table is at

On 2016-07-29 03:16:53.700632 by Ray

We have a well, water pressure not good is there anything. I can do or must I have a plumber

On 2016-07-28 16:02:57.461175 by (mod)

Curtis please search InspectApedia for WATER PUMP SHORT CYCLING to read the probable cause and cure of what you describe.

On 2016-07-28 09:38:08.914393 by Curtis Barnes

My pump has been cutting on and off rapidly. I installed a new pressure switch an set it by directions in box. Workked fine for 2 days. Has now quit and the points are closed and I have voltage going into pump but it doesn't run.Pump is not very old , what could be my problem ?

On 2016-07-18 16:43:07.513472 by (mod) - water hammer problems and vibrations

Vidula please search InspectApedia for WATER HAMMER to read the common causes and cures for the problem you describe.

Yes it's probably worth installing a water hammer arrestor, but also check the house-side pressure of your water system - that is the house side of the pressure regulator - to be sure that it's working properly.

On 2016-07-17 20:38:00.533892 by Vidula Damle

I am in Philadelphia suburbs and living in the house for the last 8 years. I have a 3/4inch water line that has the pressure regulator.

For the last two months, there is a hammering/shattering noise that comes every time I open or close the faucets or flush the toilets. There are vibrations coming from the supply line. As a first measure, I tried adjusting the pressure regulator by turning it anticlockwise 2 times to reduce the water pressure.

Also I tried to drain of the system by turning off the main and flushing all the faucets and toilets and turning on the mains back again. However there is no appreciable change. Please guide me with the following questions:

1. Is it the pressure regulator (watts 25AUB with filter) that needs replacement (a quick fix) or there could be other problem ?

2. Is it worth putting on a water hammer arrestor? If yes, what should be the location

3.What work should I expect from plumber if I need to hire one?

On 2016-07-04 17:04:47.643451 by (mod) - hot and cold water pressure are not the same

Matt when cold and hot water pressure are different the problem is not a system wide issue (such as a bad pump) it is instead going to be traced to a clogged or partly-closed valve, tankless coil, etc.

Some lower or weaker hot water pressure is common if the water heater source is a tankless coil, though as that pressure continues to weaken I'd look for a scale-clogged coil.

On 2016-07-04 15:06:39.373121 by Matt

Replaced an above ground pump with a submersible and now I have weak water pressure.

Especially hot water it just trickles out. Any ideas?

On 2016-06-09 15:52:15.231897 by (mod) - using a water pump without a pressure tank

THere are tankless water pump systems that include a control to avoid short cycling.


On 2016-06-08 16:44:20.302446 by doug

can a jet pump be used w/o a pressure tank...? such as the piping going directly to a faucet attached very close to the pump.... I've got a bit of a short cycling issue where the pump is coming on and going off rapidly.... thanks Doug

On 2016-05-30 20:43:10.453552 by (mod) how much pressure tank air pressure pre-charte is right


set the air pre-charge to 2 psi below the pressure switch cut-in pressure. 60 psi of air is probably waaay too much.

On 2016-05-30 19:31:48.792684 by Anonymous

My pump keeps recycling and the water keeps stoping.I have 60# of pressure in air tank

Water Pump Control Switch Article Series Contents

Question: Should I be using a 30-50 psi switch when running 38-64 psi cut-in/cut-out? Should I change the air pre-charge pressure in the water tank?

I have a 20 gal wellxtrol with a 30-50 psi squareD Pumptrol switch with pressure reading that are unusual. The pressure switch needed replacing because contacts were sticking. I put in a new pressure gauge and measured before I replaced the switch: tank pressure 18 psi, cut in 42 psi, cut out 67 psi. The system seems to work fine. It's 25 years old.

I replaced the switch with the same, and adjusted it to 38 psi cut in, 64 psi cut out. Do I need to increase the tank pressure to 36 psi? Should I be using a 30-50 psi switch when running 38-64 psi cutin-cutout? - D. Hurry

Reply: The 30-50 psi pressure control switch is acceptable. Set the water pressure tank air pre-charge to 2 psi below the cut-in pressure

D Hurry:

First, if your present pressure control switch is handling your (somewhat high) setting of 38/64 psi cut-in/cut-out you don't need to change the switch itself. Square D's pressure control switches typically can handle pressures up to 220 psi - much higher than a typical residential water pressure tank setting will ever be.

In the article above we list the factory air pre-charge settings for models of Well-x-Trol water pressure tanks.

Please read the WARNINGS about messing with tank air pre-charge in the article WATER PUMP PRESSURE CONTROL ADJUSTMENT

Then you can set your pre-charge pressure (with all water drained out of the tank) to 2 psi below the cut-in pressure on your pressure switch, or as you suggested, for a 38 psi cut-in, you'd set the air charge to 36 psi.

That 4 psi difference, however, is not very significant. Leaving the tank at factory pressure and setting the pressure control switch to a higher cut-in/cut-out pressure means that the volume of water you can draw from the tank before the pump turns on is a bit reduced.

Details about how to adjust the water pressure control switch are at different pressure ranges?

I just had a well switch replaced but now I have low water pressure. The pressure switch is set for 20/40 pressure and I know that the previous switch was set to 20/50 psi on and off.

The plumber says the swich is pre-set and that's it! But looking at your website I see that one can re-set the pressure switch.

I am 60 yrs old and a widow and will try to do this myself as i saw your info on tightening a nut inside that gray box that the plumber put on.

What i want to know is that one CAN change the pressure on any and all pressure switch boxes? or is it true you have to order anther box preset for the pressures i had? ALSO i have a blue water tank with a bladder - how much pressure will be too much? - E.S., Louiville KY 10/14/2013


When the plumber said the switch is pre-set to 20/40, s/he's right that that's how the switch came from the factory

But most pressure switches permit a limited range of adjustment or fine tuning. We discuss this in the article above.

But again, one does not usually need to mess with the pressure settings, and often, as I elaborate below, often when we're not satisfied with "water pressure" we ought to be checking for obstructions that reduce the water flow rate before just blithely upping the pressure settings.

Typically a 20/40 psi switch could be set up to a 50 psi cutoff and work OK, but if you set the pressure higher than your pump can reach the pump will just keep running;

Watch out: I would not set the pressure over 50 in any case; both to protect the pump and to avoid overpressurizing the tank.


Also let's be sure we're talking really about pressure, not water flow rate. Pressure is measured as a static condition - how much pressure is in the system when water is not running.

Water pressure alone does not make for great flow rate at the plumbing fixtures.

Picture trying to push 70 psi water (measured with the pump off at the end of a pump-on cycle) through a pinhole-sized opening at a clogged faucet opening. You're still not going to see much water pouring out of the faucet.

When you open a faucet, what people loosely call pressure is properly called flow rate - how much water comes out of the faucet per minute. Indeed upping the pressure switch setting increases the flow rate, up to a point.

But if you are not satisfied with flow rate, other factors should be checked, such as clogged faucet strainers (common especially after work has been done on a plumbing system as we may have stirred up debris); and clogged piping due to mineral deposits (usually first detected in hot water lines).

For some tips also

Question: now many turns of the adjustment nut make how much change on a pressure switch?

(Sept 22, 2014) Anonymous said:
Pete how much turning in degrees of the pressure spring nut are we taking about. approx.



Try a 1/2 rotation to one full rotation of the nut you are changing, then observe the pressure response change in the system.

This is not lab-grade precise equipment nor are the effects of adjustment nut rotation degrees consistent throughout the adjustment range.

Question: warnings about limits of the smaller pressure switch nut adjustment range

7 March 2015 Andy said:

Near the top of thisPRESSURE SWITCH NUT ADJUSTMENTS article, it says: 'Watch out! If you loosen this nut too much you can set the cut-off pressure below the cut-on pressure and the pump will turn on and run forever (or until it burns up.)'

This doesn't make sense. If you back the differential nut off 'too much', all that means is that the differential will be at its minimum which might cause short cycling. shortcycling is of course damaging too, but the pump can't fail to shut off if the main spring is set anywhere near the standard and all other things are normal. What am I not getting here?


Thank you Andy, you're right and we're deleting the confusing text. We appreciate your careful eye and can use all the editing help we can get.

After adjusting nut #2, the smaller nut that in most of these controls adjusts the differential between cut-in and cut-out we kept this warning

Watch out: After adjusting nut#2 you may need to check the actual operating water pressures in your system and adjust nut#1 to be sure that you are not pushing the cut-out (upper pressure) so high that the water pump never turns off (dangerous).

As your comment points out, an additional caveat could be added: don't set the differential between cut-in and cut-out too close or the pump will short-cycle.

A different error would be to set the Nut #1, the larger adjustment, cut-out pressure too high.

That's a common mistake that some folks make in trying to get the highest water pressure possible in their building. The result could indeed be a pump that never shuts off and that burns up.

Question: I'd like to get the cut-on at 60 and cut-off at 70 to get very high water pressure

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: watch out: setting the differential too small causes short cycling & setting the cut-out too high may exceed the pump's capacity, burning it up

Ben, please take another look at the details in the articlePRESSURE SWITCH NUT ADJUSTMENTS 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.

Question: I want to control water supply to different areas of our factory through Inverter drives

Photograph of a water pump pressure control switch with the cover on

I want to control water supply to different areas of our factory through Inverter drives , pressure feedback in order to simultanously achieve energy saving,equal pump running hours(There are 3 pumps with common header).

There shall be bumpless transfer of pumps so that there is min. pressure surge. Can anyone give me solution - Mehboob Akber 5/21/11



I'm not sure what inverter drives you are talking about, but for general water pressure control to set different water pressures in different building areas,

and provided that the base water supply and delivery system has adequate pressure and flow capacity, you would need individual pressure control tanks, pumps and switches, or for a simpler arrangement, simply a pressure regulator installed at the inlet to each factory area.

Lightning Strike Effects on Pump & Pump Switch

On 2017-03-16 16:42:39.685467 by (mod) - lightning strike at pump can give weak pressure

Curious, Ez.

If your power outage was caused by a lightning strike the pump or pump wiring could have been damaged. Some well pumps that intend to run at 240V might limp along at low voltage. So I'd start by asking your electrician to check the voltage being supplied to the pump and its controls.

Keep us posted; what you learn will also help others.

Matt: Please search for INTERMITTENT LOSS OF WATER PRESSURE to read the diagnosis and cure of the problem you described.

On 2017-03-16 04:47:32.355493 by Ez

Private water bore - We had a power outage for several hours (electricity company updating their system) and since resumption, the water pressure is lower.

I noticed it because the hot water pressure is half of what it was before the outage, the cold is always strong and is more than adequate (but not strong enough to push the hot water at a reasonable flow).

I know virtually nothing about how this all works except I have a submerged pump located several meters from the house in the garden. in the loft I have a large plastic storage rank, a large 3' pressurised metal tank with a gauge on it, and an electric box with LEDs that cycle on and off;

in a cupboard I have a pump on and off switch, a pump isolator switch, and switch labelled by the previous occupier as 'overload switch'.... so where do I start to diagnose the problem? Thanks

Pressure Control Switch Noises: Buzzing, Clicking, Humming

Question: humming water pressure pump control switch

My water Pump Pressure Switch seems to be emitting a low hum all of the time It sounds sort of like you hear around electrical transformers. This is a new thing for the unit. My electric bill has also been high and my water pressure is intermittently low.

I can make the hum stop by pressing on the plate that's connected to the springs. It sparks when I do this. Yikes! I suspect that the switch is stuck in the on position. What do you all think? Thanks! - James 11/27/12


James, the pressure control switch might click on and off, but humming?

First - make sure that the sound is coming from the switch itself and not from nearby water piping or from a nearby pump. Well pumps are not silent, and pump noise can be transmitted via water piping.

Second - if you are convinced it's the switch, if tightening the electrical connections at the switch doesn't fix it (do this with power OFF) I would replace it promptly.

The pump relay is an electromagnetic switch. If it is humming and vibrating it is probably failing and you're about to have

Watch out: I wouldn't keep pressing on the relay. There's live 120V or 240V in that switch - touching exposed wires or connectors is asking for a potentially fatal shock. Keep me posted, what we learn will help other readers.

See the diagnosis & repair advice at WATER PRESSURE SWITCH NOISES - what causes humming or clicking noises at a building water pressure control switch: diagnosis, warnings, advice.

Also see WATER PUMP / SWITCH NOISE FAQs for some diagnostic questions and answers for noises traced to the well pump, pump controls, or water tank.

Question: after replacing pump and pressure tank the pump switch keeps clicking

relay switch on water pressure device clicking when water is being used why and what is the fix please. - Anon 9/30/12

i replace my pump and pressure tank. but when i turn on my water. i here the pressure switch go click click click non stop when i turn on water - Jerry 11/16/12



Watch out: If the clicking pressure switch is switching the pump on and off very rapidly, say every second, TURN THE PUMP CIRCUIT OFF immediately to avoid damaging the equipment. Then check for a clogged water filter, a water valve that should be open is closed, or a waterlogged preside tank


It is normal for the relay switch to "click" on and off when you are running water continuously.

It's a sound that folks don't notice if the switch is right next to a (noisy) well pump, but when the well pump is submersible (located in the well) the pressure control switch click may be about all you hear.

If the clicking is rapid - see my warning just above. If the click occurs say once every 30 seconds, that's normal. It's the pump switching on and off as pressure falls and rises.

Water Pressure Control Switch or Control Panel Diagnosis

Question: pump control panel overload message

(Feb 17, 2015) jeevan said:
in my control panel it is displayed over load


Check the instruction manual for your pump control for details. Most likely you're being told that the pump is drawing excessive current, indicating a short, wiring failure, failing pump impeller or bearings, or clogged intake screen.

Lost Water Pressure FAQs: water pressure slowly falls to zero or stops completely, returns, or does not return later

Question: lost water pressure, came back on its own, plumber replaced presure switch.

I had a Plummer come to my house on the week-end since I had lost pressure for my water. When the plumber arrived the pressure was restored but since the system was 21 years old, I decided to have him replace the switch. If I remember I had a 20-40 pressure switch that was adjusted to 40-55 so that when taking a shower we would not notice the low pressure.

When the plumber installed the new pressure switch 30-50 I asked him to adjust the pressure and that is what he did. He adjusted the pressure with the bigger nut as explained in the WEB site, so now the cut-in pressure is about 32 and the cut out is about 58-60.

The problem is that when someone is taking a shower the cut-in rating is to low so the pressure is down. What steps can be done to increase the cut-in pressure but keeping to cut-out pressure to about 60….

So I could have something like 42-60 or so if possible. Thank you - Andre 10/25/11



Please take a look at the pressure switch adjustment information in the article above.

You'll see there are two adjusting nuts in the control. Basically the larger nut shifts the whole operating pressure range (cut in and cut out) up or down while the smaller nut adjusts the differential between the cut in and cut out.

You can adjust the smaller nut to narrow the differential if you like - just don't make the cut-in too close to the cut-out or your pump may turn on and off too often and overheat.

Question: lost water pressure in freezing weather

(Feb 22, 2015) Cindy said:
how do I know if my lose of water is my pump pressure switch or my pipes are frozen?




Because is number of failures all result in no water.

In general, if the system was working and then stopped during very cold weather it's natural to suspect frozen piping. Turn off the pump to reduce the chances of riuining it.

If the pump is above ground you can determine that it's running by inspection. If its in the well some electrical tests can do the same.

Question: lost water while watering the garden

I just moved into an old farm house I was watering my garden when I lost water, I had run it for some time. did I use up all the water?

I went to the pump imediatly and turn off the water spicket. did I burn up the pump, I don't get great pressure in the house since I moved in.

later I got a little water but then it was gone again. what can i do to find out what happened - Sandra 6/5/11

Bladder tank set at 30 psi switch set at 40 psi cut off. I have water but no pressure. help - Charlie C 6/7/11



You need a well flow test or an approximation of one so that you have an idea just what your well can deliver. If the well flow rate or recovery rate is limited you can drill a new well (expensive, no guarantee of success) or add a larger quantity of water storage in tanks.

But be sure you've accurately diagnosed the poor flow rate; poor water pressure or flow can be caused by clogged piping, for example, or you may have both problems: clogged pipes and a low-flow-rate well. - DF


if you have no water pressure at all I think you may best take a look at the diagnostic guide in theWATER PUMP DIAGNOSTIC TABLE

Question: water pressure slowly falls to zero, recovers after about 45 minutes

(Apr 1, 2014) Ray said:

The water at my home runs for about 5 to 8 minutes then it slowly stops. I turn the sink back on and still no water, after about 45 minutes I have water again what could be cause

(Apr 2, 2014) John Hernandez said:

I purchase a DAB water pump i'm having a problem with cut in and cut off the pressure guage needle drops to zero before it cuts in i tried adjusting it no results.Can you help me?

Reply: signs of a debris-clogged water pressure control switch sensor port or pressure gauge

Ray, Check these two key diagnostic approaches

your well may be running out of water but it makes sense first to go through the diagnostic steps suggested in those articles.

Check to see if the pump pressure switch sensor port on the switch bottom, or its mounting/pressure sensing tube are dirt clogged. There could also be a sticking relay. In those cases replace the switch and its mounting tube.

Question: dirty water, pump won't shut off

(Mar 29, 2015) M A Rizvi said:
Boring 4" depth 180ft Pump located at 90ft but water is dirty (sand & mud). Pump is running continuously since 12hrs but discharge is not clear. Boring location is Husainabad,Lucknow. Please advise.


Your well flow rate or pump are unable to satisfy the pressure setting on your pump control. Or perhaps the debris has clogged the pressure sensor port on the pressure contorol switch. You should turn off the system before ruining the pump. Then check for debris clogging.

Turn off the pump to avoid burning up the motor.

Question: water pressure goes down to next to nothing

(May 2, 2015) carl mcevers said:
water pressure goes down to next to nothing after a few seconds of turning it on


Sounds as if there is a waterlogged pressure tank and a slow-flow or low capacity pump. Clogged or very small diameter piping combined with low water pressure can have this effect as well.

Question: water pressure falls immediately from 60 down to 40 and pump cycles on and off

(June 24, 2014) Anonymous said:

My pressure is set at 60 to 40, When you turn the water on it drops from 60 to 40 immediately and will continue to turn on and off until the water valve is turned off. The pump basiclly want shut off until you stop using water

Anon when pressure drops immediately on opening a tap I expect that there is little or no air charge in the pressure tank.

Take a look at


No water and no pump working following a power failure

I had a power failure today and now that the power has returned I still don't have water. I reset the breakers just in case with no effect. The pressure gauge next to the switch still says 50psi but no water is coming out of the taps. Never had a problem with this system before.

It is a pumptrol like in your picture. It doesn't have a lever on the side like I've seen in other pictures. Any ideas? - Alex D 8/18/11

(3 days ago) Anonymous said:

Have square D pressure switch 9013FSG2M4 on 1 hp elect pump; water from aireator to house through 35gal pressure tank (rubber diaphram). works fine normally ( 35psi to 55psi) except when lose electricity.

If pressure drops below 20psi before the electricity returns; when elect. returns pump appears to start but switch contacts open. I have to hold contacts closed until pressure builds to 30 psi for them to stay costed. Why? What is solution?



Following a power failure or a lightning strike there are a number of possible sources of well and pump trouble. Starting with the clues in your question.

As your gauge says your system is at 50 psi but yet you have no water coming out of the taps, I wonder if the pressure gauge (and thus potentially the pressure control switch too) are dirt clogged and not registering pressure changes - try tapping on the gauge to see if it moves; replace a clogged gauge, pressure switch, or mounting pipe nipple or plastic line feeding water pressure to the switch sensor.

Have your electrician or other expert check for the presence of voltage at the pump and control switch

Check for a lightning strike that shorted wiring, burned wiring, or damaged the pump motor - see


It sounds as if the electricity loss means you are losing prime in your pump - check first for a bad foot valve or check valve.

Water Pressure Lost Completely

Question: lost all water pressure

(July 8, 2014) tony said:

i have lost all water pressure. when i turn the mair valve off the press gauge will go up to 40psi. however when the valve is opened the gauge goes to pressure switch about 2 weeks old.

On 2016-09-29 15:53:20.329621 by Anonymous

I have no water at all



We give lost water pressure diagnostics at

For the case you describe, turning the main valve off is stopping output from the pressure tank into your building.

As you see water pressure with the main valve off, that suggests that water is running in your building or there is a burst pipe - but that's just guessing from your brief question.


On 2016-09-29 by (mod)

Anonymous: please search for NO WATER PRESSURE to see a recommended list of checkpoints and repairs to fix the trouble.

Anonymous on Sept 3: search InspectApedia for PUMP WON'T STOP RUNNING to see how to diagnose and cure that problem.

Question: water pressure is low but the water pump won't come on

Pump won't come on: I just changed the pressure control switch and it will not turn on by itself. the water pressure is very low but the pump never comes on. - BigEd 7/16/11

The pump will not come on. There is no water pressure. I have a Square D Pump Pressure Control Switch. The contacts will not stay down/connnected. When forced to on postion they bounce right back into off ppostion. Any advice would be helpful. - Wilson 7/31/11

My water pressure is very low after one or two loads of laundry. The pressure gets down to less than 15 and the pump still has not pumped. I am not sure how low it gets before it pumps. Whan I get up the next morning it is back up to 45.

What might be the cause of this problem? Is it the pump pressure switch or something else. I hear it running all the time. Any advice would be helpful - Mark 8/31/11

We are losing water pressure at any/all faucets/toilets/etc randomly- water will be running fine, and then it will slack off to nothing, then within 30sec to 1 minute, water will come back one and be fine. This happens at least once a day.

This also just started happening once we replaced the entire reserve tank and pressure gauge and switch (we had a drip from our old tank, and a plumber came in a replaced the whole thing). Now he tells me he thinks this new problem is the well pump....seems very convenient to have 2 major things go bad at exactly the same time. What do you think? - Meg 9/2/11


Big Ed

Sometimes changing the switch but mounting it on the existing 1/8" support pipe or connector to the pump or piping leaves a clogged component in place so that the switch doesn't properly sense the actual water pressure.

If your switch is properly wired and there is power to the pump, that clogging could be the problem.


if the pump pressure control switch has electrical power and won't stay in the "on" position, that suggests that the pressure diaphraghm of the switch is indicating pressure at or above the cutoff point. If in fact there is no or low water pressure in the system then perhaps the pressure sensing end of the switch or its mounting tube is debris clogged. R&R the switch and mounting tube.

In a different direction, if someone messed with the adjustment nuts on the pressure switch they could have left it in an improper setting position.


what you describe sounds like your well recovery rate is poor, perhaps seasonally during hot dry weather. Under WELLS CISTERNS & SPRINGS (links at the "More Reading" links at the bottom of this article ), see the article titled "How Much Water is In the Well?" for help in investigating that question.


I too tend to look first at work that was just recently done, or what was just changed, when debugging a building problem that has just shown up.

I tend not to start by blaming the pump, though there could be an indirect cause there: if the plumbing changes increased the water usage rate or the rate at which the pump was asked to operate, a pump motor that was overheating (failing) might on occasion turn itself off on thermal reset then reset and begin again automagically.

But before replacing the pump I'd look more closely at the pressure control switch; for example, if the plumbing work stirred up debris in the system, crud could be blocking the pressure sensing input of the pressure control switch, causing it to misbehave.

You could try removing the switch, replacing or cleaning the small diameter mounting tube for that device (where water flows up to push on the switch bottom), and if necessary replace the switch.

See the water pressure loss diagnostic steps at WATER PRESSURE LOSS DIAGNOSIS & REPAIR (article link at the "More Reading" links at the bottom of this article )

Keep us posted - it'll help other readers

Question: How to increase the water pump pressure control cut-in and cut-out pressure

I have a square d control. It cuts off at 40 psi and goes down to 20 psi before it comes back on which is to low when I am using one sprinkler. I want it to come on at 30 psi. I can't understand how to do that looking your directions. Pls help - John 5/19/11


How to increase the water pump pressure control cut-in and cut-out pressure:

Take a look again at the instructions above that indicate which nut to turn in which direction to increase the well pump cut-in pressure (that's your 20 psi number) and cut-out pressure (that's your 40 psi number).

You should be able to raise the cut-in pressure to 30 psi and you will probably want to raise the cut out pressure to 50 psi, provided that your pump can actually reach that number. If the pump keeps running forever even AFTER you have turned off the water, then it is not capable of reaching 50 psi and you'll have to lower that setting to avoid burning up the water pump.

If the instructions are still too complicated to follow then you would be best off asking a plumber to change the settings for you. Just be sure the person you hire is familiar with well pump pressure control switches.

Question: 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


Ben, please take another look at the details in the article above 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.

Water Pump Won't Stop Running - what to do

Question: my pump cannot reach the cut-out pressure setting - my pump runs all the time

I have replaced the Pressure swtch and I can not acheive cutout, pump continues to run. Switch is adjusted very low for cutout. The units cuts in about 26-28 psi. but exceeds the desired 50 -60 psi cutout. - BK 6/6/11

I had to put a new pressure switch on, the pump was running all the time and it burn the points up. The new one is letting the pump run all the time too, when the pump is running the water pressure keeps going up and down, until there is a small amount of water coming out.

I'll turn the pump off and back on then the pressure will come back up and if it runs about a couple of minutes it will do the same thing again. I have no leaks, could this be the water tank?
I need help - Ed 6/18/12

My pump does not exceed 32psi and constantly runs then fails to cut back on even though pressure drops below 20psi. Only way to start it is to manually connect the flow switch to engage the pump. - Jack Nelson 7/7/12

(Nov 26, 2014) Evelio said:
water pump in the tank keep and pressure wont go over 40psi theres anething i can do

(Jan 26, 2015) Anonymous said:
pump does not shut off


BK: Well pump won't stop running: try setting your pressure control to turn on at 20 psi and off at 40 psi. That should be achievable by most well pumps unless the pump itself is damaged. Once you have the pump operating normally in that pressure range you can try increasing the cut out, or both cut-in and cut-out gradually

Don't operate the pump too close to the highest cut-out pressure that it can attain, since there is the risk that when you're not watching the system may through wear or other factors leave the pump running until it burns up.

Jack, if the pump does not start at pressures below the cut- in point of 20 psi, the switch may be bad. But the pump running continuously and never delivering cutoff pressure is something else _ such as lost well water flow rate or a well piping leak or someone has lest a faucet open in the home.

Evelio, check for a well running out of water or a worn or damaged pump impeller or low voltage to the pump motor.

Question: pump won't stop running and got very hot - my well pump won't turn off

Pump has worked fine until today for some reason it kept running after the 'timer' stopped. I didn't notice for a while and by the time I got to the pump, it was really hot. I killed the power and water/steam shot out of a PVC pipe on the bottom. If I plug it in, it won't stop running.

I turned the timer on and tried to send water to a sprinkler zone to no avail. Please help! - pumpwontstop 6/17/11

I have been having a problem with my well for a couple years now with it staying running. I hired a well guy and he told me it was a 30 year old system and it needed to be replaced, so i started to replace things and it has fixed some problems, but has cause others.

We replaced the air tank, pressure control switch, the run capacitor, and the start cylinder.

When we turn it on after about 4 hours it will run for 5 to 10 min, but if we let it sit off for 8 hours or even 10 hours it will run for 15 to 20 min. I have no clue what is going on and seeing if someone could help.

Also as I was down at the well, and it was turned on their was some sloshing in the system as it starts and turns off. If you need any more details just ask. - Mike 7/25/12


If your well pump won't stop running and it is delivering water then I suspect that the pump is unable to reach the cut-off pressure.

That can happen for a variety of reasons like loss of water in the well, a well piping leak, water running somewhere that you didn't realize, a pressure switch set too high, or a damaged pressure sensor component of the pressure control switch.

see WATER PUMP WONT STOP RUNNING for a thorough diagnostic procedure


If the pump runs all the time even when you turn OFF water from the pressure tank into the building, then since you've excluded the control itself:

- the pressure sensing port on the pressure switch may not be seeing actual water pressure if the small diameter tube or pipe feeding pressure to the switch is clogged

- you may have a leak in well piping in the well or in the ground between house and well.

- you may have a damaged pump impeller that is not developing enough pressure to reach switch cutoff

- or something else

Hi Mike. It sounds as if perhaps you are losing well prime back down into the well - could be a bad foot valve - or a leak in the well piping.

Is the pump in the well or above ground? If above ground, is it a one line or two line jet pump?

Followup from Mike:

the pump is in the well about 600 ft down how do i find a leak that far down or where is the foot valve in the pump? thank you for answering me fast


Mike, first establish that there is a leak, and in what segment of the whole system it exists - say in the building vs between the water pressure tank and the bottom of the well.

If it appears that the leak is in the well piping and if the leak is in the well piping that's in the well itself (as opposed to between well and building) you're in luck because you can pull the whole well piping and pump (use a professional to do this) to find and repair the leak as well as replace the foot valve.

If the leak is between house and well then unfortunately excavation is in order.

If the leak in the well pipe is in the well and is between the water surface and well top, you'll hear or even see water squirting out of the leak when the pump is running; if it's under-water you may never see it without pulling the line.

All of this means that you start by determining that the leak is between house and well.

Search InspectApedia for

"find leak in well piping" to find our diagnostic article

Question: my pump would not stop running - the tech says I need a new drilled well

My pump began running non stop and when the well person came out they said they were able to set psi to 38 and the pump would shut off correctly however most likely the jet is plugged or a hole in casing for it to change suddenly and It will eventually just quit.

Does this sound correct. It is now functioning fine at 38 psi but I am concerned since winter is coming and I shoul get a well drilled now. I am not planning in investing in repair if it needs repair because it's an old 2" - Amanda 8/26/12


Amanda I don't understand the question you are asking. A hole in a well casing may admit dirt and contaminants and might speed up clogging of the well screen on a foot valve or pump pickup; But some more accurate diagnosis is needed before drilling a new well.

Pump Control Switch Air / Water Tube Use & Connections

On 2016-09-02 14:55:20.662297 by (mod) - where to hook up the air tube on to the pump or control switch


All pressure control switches need a connection to a pipe or tube that conducts water pressure from the water system to the pressure sensor port on the switch.

Actually the tube (or small diameter rigid pipe or pipe nipple) will normally contain water, not air, though a bit of air in the tube usually won't affect the switch operation.

The instructions that came with your particular switch will show where that connection is located: usually it's on the switch bottom plate and usually it's a simple 1/8" or at most 1/4" NPT threaded fitting.

Find the old pressure tube or pipe to which your prior switch was connected, and connect that to the new switch.

Pressure switches usually mount in one of two ways: either the switch is mounted directly to the pressure communicating tube or pipe - in that case a 1/4"or 1/8" npt rigid pipe, typicaly 1-4" long.

The switch mounts on the exposed end of the pipe (properly called a nipple as it's short and threaded), and the other end of that nipple is screwed into the pump or piping where it can receive water and thus pressure.

Other pressure switches are bolted to the pump through a bolt or screw fitting, or may be mounted anywhere nearby.

On those switches a flexible tube, either flexible copper tubing on older systems or plastic on newer systems, connects to the pump or piping and to the switch to convey water pressure.

On 2016-09-01 23:18:44.430511 by Bubba

Changed brands of pump where do I hook the tubings have air control valve on tank where do's it mount on a Pentair pump .

where does the tubings go one on bottom of regulator and where does one from regulator mount O pump ?

Water Pressure & Water Pump Article Series Contents


Continue reading at PRESSURE SWITCH NUT ADJUSTMENTS or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.

WATER PUMP PRESSURE CONTROL ADJUST FAQs2 - second set of questions & answers on adjusting the well pump control switch

Or see WATER PUMP PRESSURE SWITCH REPAIR FAQs - pump control switch diagnostic & repair questions & answers



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