Water pump short cycling diagnostic FAQs:

This article provides answers to frequently-asked questions about how to diagnose short-cycling problems with a water pump or well pump.

If the well pump runs too often or cycles on and off rapidly these diagnostic questions should help troubleshoot the problem.

Questions & answers about well pumps or water pressure pumps that run too often (short cycling)

These questions and answers about troubleshooting and fixing a well or water pump that keeps turning on and off rapidly were posted originally at SHORT CYCLING WATER PUMP - home - be sure to read the procedures and repairs discussed there.

Question: surging water pressure cause & cure

(Jan 20, 2013) Sam said:

We are in the process of changing the water pressure tank. I noticed yesterday that when running water we would get a blast of strong water then it would go back to normal.

It does seem to be waterlogged. Would this cause it or do we have a bigger problem with our submersible well pump?

Reply:

Sam, I suspect that you are seeing the surge in pressure when the water pump is running, and the more modest pressure when water is being delivered by air pressure in the water pressure tank. I'd start by draining the tank and making sure it had a proper air charge.

Question: Pump runs 60 sconds on toilet flush but runs continuously with other uses

(May 5, 2014) H20 said:

when we flush the toilet or Use the kitchen Faucet the pumps runs for exactly 60 seconds but when we used the washing machine or Take a shower it runs continuously or until the water is turned off then it runs a Min longer before shutting off . i have a 2hr starite on a 30 gallon flotech.

Reply:

H

When your system is drawing water at a fast enough rate the pump will run continuously and flow rate will be ultimately the pump's capacity.

When your system is drawing water at less than the pump's total output capacity the pump will "get ahead" and will be able to raise pressure in the system to the cut-off point set in the pressure control switch.

Check your tank and pump frequency to decide if it's short cycling - as described inWATER PUMP SHORT CYCLING CAUSES

Question: short cycling well pump, very short on cycles, no pressure tank

5/18/2014 ohwell said:

i had a house fire 2 years ago..well pump has not run since today..i had my well pump directly wired from the temp power pole to the pump feeding a wellstand..pump goes on and off at 10 second intervals ..i can hear it down the well pipe..water will run sometimes as the pump cuts in..well is 100' deep..water was brown at first and seemed to be strong untill pump started cutting out..did well pump sit to long??

Reply:

OhW

It sounds as if your pump is short cycling for one of the rasons discussed in the article WATER PUMP SHORT CYCLING CAUSES.

Take a look at the ARTICLE INDEX at the end of this page and try one of these two diagnostic articles

SHORT CYCLING CAUSE: WELL PIPE LEAKS

SHORT CYCLING DIAGNOSIS TABLE

Follow-up

ohw said:

i discovered today the pump comes on for about 4 seconds full blast and then cuts out for approximately 40 seconds then repeats..i have 30 amp breaker on it..theres no pressure tank..system was configured for a pressure system..im in the process of rebuilding and just wanted to have water for my RV on construction site..i have a simple plug for a switch to turn the well pump on and off..will read the topics you suggested..thanks

after reading the links above im still at a loss still for the reasons ive explained..the system was perfect before the fire..i cut excisting hose shorter in case of blockage and moved the water line over to the side of the property where i put an 8' wellstand 4'up/down..i have a call into the local guy here..its the long weekend still..i will give him a call again tommorow

Reply: no pressure tank?

OHW
Well thanks for reading the links I suggested.

You are describing short cycling; I'd be quite interested if we've come up with another cause that's not been cataloged.

When a water pump is "on" for only 4 seconds I suspect that it's pressurizing the system to the pressure switch's cut-off pressure too quickly. Typically that's caused by

- a waterlogged pressure tank

- a water filter that's dirty

- a clogged outlet at the piping or tank

- a water tank bladder that's stuck to itself, not admitting water into the tank

On odd occasions pump behaviour such as you describe could be caused by debris clogging the pressure sensing port on the switch.

When there is NO pressure tank, as in your system, it'd make sense that the pump would run only for seconds before reaching the cutoff limit.

Short cycling the pump risks burning it up.

Question: pressure goes up and down fast

(June 26, 2015) pozzi said:
when water is running the pressure goes up and down fast

Reply:

Poz you are describing classic well pump short cycling that is usually caused by one of the problems described beginning at WATER PUMP SHORT CYCLING CAUSES

Or if you want a more concise diagnostic guide to short cycling pumps see WATER PUMP SHORT CYCLING DIAGNOSIS TABLE

Question: water pressure goes up and down

(July 15, 2012) me said:
i have drilled well. when pump runs it will have up and down presser then will shut its self off. bought a new one replaced it
and the new one is doing the same. checked everything.

Reply:

Me: Well we must not have checked absolutely everything or the problem would not be continuing. You didn't indicate what type of pump nor what's in the well.

For example, if a well has a poor flow rate a tailpiece in the well, intended to prevent the pump from burning up by pumping dry, will reduce the pump output to the house when water level drops below a certain point in the well - that alone can cause variations in delivery of well water; So can voltage swings, sticky check valves, &c. I'd ask for help from a professional at this point.

Question: pump runs as soon as we flush the toilet

3 July 2015 AUTHOR: Ron (no email)

COMMENT:Have a home that has a cistern which fills up via small amount of pressure from city. We have a pump that draws from the cistern for all household needs.

We find that every time we flush the pump gets activated. We have low flow toilets that consume about a 1.5 gallons per flush. We only notice pump running mostly after flushes.

Is the pressure tank too small. Tank looks to about 4 gallons. Can a bigger tank be used? Thank you in advance for any info. Here is a picture. [Above - click to enlarge any image]

Reply:

Except for "tankless" water pressure booster pump installations, a water pressure tank including the one I think I see at the right in your photo should certainly give more total draw-down in gallons than that needed to fill a toilet. Typically toilets are using from 1 to 3L of water while the draw down volume should be 2-4 times that. So more likely your water pressure tank is waterlogged.

The diagnostics at SHORT CYCLING WATER PUMP should be what you need. Let us know if after reading that you need more assistance.

 

Question: Short cycling well pump, bad pressure settings or bad check valve?

I think my check valve is bad, letting air back to well. Our well pump runs for 3 seconds shuts off for 3 seconds. It does this over and over. I am thinking pressure settings on bladder tank might not be right? - Tim.

Reply: Check for a bad snifter valve and/or a water-logged pressure tank

Tim:

Before trying to change the pressure settings at the pressure control switch, you should check for a water-logged water pressure tank or another cause of well pump short cycling.

Take a look at the article SHORT CYCLING WATER PUMP - usually the first thing to check is loss of air in the pressure tank; it's true that a bad foot valve or check valve that causes water to bleed back into the well (and thus the tank pressure to drop) can cause the well pump to cycle more often, but that alone wouldn't get us to cycling every 3 seconds. That's more likely a lost air charge or a clog that is not letting the pump get water into the pressure tank;

The relation between lost air charge and lost well prime might be that in a bladderless pressure tank system the more often the well pump cycles the faster we lose the air charge in some pressure tanks.

Also, if your well uses a submersible pump and a water tank that does NOT use an internal bladder, your system may include a snifter valve that is supposed to be letting air into the well piping - as a means of keeping the air charge in the water tank. If the snifter valve has failed (as they can by debris clogging) that could explain a waterlogged pressure tank and a short cycling well pump.

• Snifter valves and other devices intended to automatically keep the required air in a bladderless water tank are explained at AIR VOLUME CONTROLS, WATER TANK.
• Causes of pump short cycling are at WATER PUMP SHORT CYCLING CAUSES.
• Procedures for replacing lost air in the water pressure tank (a common cause of short cycling pumps) are at WATER TANK AIR, HOW TO ADD

Comment: Draining the water tank, adding air, and adjusting the pressure control switch solved the short cycling water pump problem

Bob said:

Problem: Pump cycling every few minutes for months....Your question and answers solved my bladder type pressure tank cycling problem. I drained the tank and added air to 28 psi (was below 20 psi). I filled/pressurized tank and adjusted limits to 30 (low) and 50 (high). And WOW, now it takes 5 toilet flushings before pump kicks on.

I tested the pressure tank psi after pump clicked off and my gauge read 53 psi. So my problem was low air in the pressure tank and limits out of adjustment. Thanks for your instructions that anyone can follow and it saved me lots of money for a plumber.

Reply:

Bob: Thanks for the nice note; we work hard to make our information useful and unbiased; I'm thrilled it worked for you; we continue to welcome questions or suggestions for our content as together we're smarter than working alone.

Question: My water pressure drops too quickly and reaches cut-out again too quickly

I have a submersible pump and a bladder pressure tank. I have the cut in at 30 and the cut out at 50. My well seem to a lot. If I watch the gauge when pressure hits 30 the pump turns on until it hits 50, but it take only a few seconds for the pump to drop back down to 30, this is with just running a faucet. Should it be cycling that fast? - Robert 7/7/2011

(Oct 23, 2012) Lori said: My water pump/tank turns off and on every 1 min 38 seconds and I hear a brief water trickle in the tank. This is when no water is running in the house. Is that low air in the tank too? or a hole in the bladder?

(Jan 20, 2013) David said: our system is extremely noisy at night. there is a continuous 'clunk clunk' every few minutes, like the system wants to come on, but changes it's mind. there is no water being used. help, my wife can't sleep.

(Oct 31, 2012) Sue said: We can hear the short cycling and what we've noticed is the pressure gauge does not move at all. Is this the problem?

(Dec 17, 2012) Anonymous said: HELP My pump comes on with every flush, is that normal?

Reply: How to tell the difference between water pressure tank is waterlogged, a leak or running water problem, and a clogged pressure control switch sensor port

• Waterlogged prssure tank: Robert and Anonymous: when it takes just a few seconds for water pressure to drop back from cut-out to cut-in pressure after the pump has shut off, it sounds as if the water pressure tank is water logged. You may have lost the air charge.

For fixing a waterlogged water pressure tank
see WATER TANK AIR, HOW TO ADD

• Water piping leak or running water: Lori & David: If no water is being run in the house and you hear water running at the tank perhaps the foot valve or chck valve is leaking or there could be a well piping leak If the pump is running periodically when you are not running water then you want to
  
  See WATER PUMP INTERMITTENT CYCLING


• Debris clogged pressure control switch & gauge: Sue: when the pressure gauge does not respond to changes in water pressure there could be a burned up contact, a damaged switch, or another problem, but most often the issue is sediment or debris clogging of both the water pressure gauge and the small pressure sensor port on the bottom of the pressure control switch. In that case we replace those parts and consider added water filtration if necessary.
  
  See WATER PUMP PRESSURE CONTROL REPAIR

This topic home page organizes key articles on water pressure diagnosis for a private well:

WELL WATER PRESSURE DIAGNOSIS

People who don't want to read explanations and just want some diagnostic pointers

see WATER PRESSURE PROBLEM DIAGNOSIS TABLE

Question: my well pump has been running more often that it should and has been louder ...

Pump has been running more often than it should & it has been louder than usual. Never lost any pressure just a little noise. Two days ago the breaker tripped. I reset the breaker and it has been fine. Again no pressure lost. This morning lost pressure and now have no water to the house at all. I checked the breaker and it was not tripped. Where do I start? - Michele S. 3/15/12

I am moving into a house that has been vacant for several years. Prior to the house being vacated, the well was operational; however, the water pressure was not consistent. It would cycle from good pressure for 15 minutes or so to low pressure for 3-5 minutes and back to good pressure.

So now it is several years down the road. I had the electricity turned on, and when I flipped the breaker I heard a sound like the electric kicking on in the control box. After about 10 seconds it clicked off. Then back on after 10-15 seconds. Then off after 5-10 seconds. And so on. It never tripped the breaker. I did flip the breaker to keep it from cycling on and off. Just wondering where to start and what to look at/have looked at. - (Mar 6, 2014) Paula

Reply:

Michelle, several problems can cause well pump short cycling on and off too often, though the most common one is a water-logged pressure tank.

See WATER PUMP SHORT CYCLING for steps in diagnosing and fixing this trouble.

Paula:

What are we seeing now Paula - no water or intermittent water?

If the switch is not turning on the pump that's one diagnostic route;

If the switch turns on the pump but you are not getting water that's a different one.

For those sorts of trouble see WATER PUMP DIAGNOSTIC TABLE

If you've got water, rapid clicking on and off of the pressure switch, if the pump is a submersible unit in the well, could be telling you the pressure tank is waterlogged. see the WATER PUMP SHORT CYCLING CAUSES link.

If you lose water for a time that could be a well flow problem OR a pressure switch clog problem. For that trouble see WATER PUMP PRESSURE CONTROL REPAIR

Paula's follow-up:

No water, no pressure. I don't believe the pump is coming on. I know nothing about wells (obviously) and am wondering if there is something to look for in a situation where everything has been off for several years. The pump is submersible (I am guessing because there is electrical wiring at the well cap). I don't believe there is any water in the pressure tank...the pressure guage reads 0 and the tank sounds hollow/empty when I knock on it.

Reply:

No water, and pump won't start: I'd start by calling a licensed plumber who has experience with pump and pump control repairs; s/he will doubtless confirm the presence of electrical power, check the pump control switch, then check the pump wiring and possibly the pump motor.

To check yourself see NO WATER PRESSURE

Question: water keeps kicking off (or turning on and off)

(Feb 25, 2014) Kathy Kerr said:

Have well water. Water keeps kicking off. New pressure switch, correct amount of pressure in tank. What's wrong? DESPERATE!

Have not taken pump out of well. Have not checked the well at all except to look down in and saw water. Have only checked pressure switch to pressure tank and made sure there is 28# of pressure in pressure tank.

(Mar 28, 2014) cherese said:

hi, I have an artesian well. my pump keeps coming on then off every 2 mins. when we checked we have no water coming into the tank. I know it's prob a problem in the well itself but what could it be?

Reply:

Kathy & Cherese,, in the event that the problem may not be the pump (though as yet I wouldn't rule out a wiring problem) you may want to take a look at

WATER PUMP INTERMITTENT CYCLING 

WATER PRESSURE LOSS DIAGNOSIS & REPAIR where we begin diagnosis of a broader range of problems. The live link to that article is in the left column near the top of this page.

Cherese I'm a little confused in that an artesian well sends water to the surface without pump pressure;

Anyway, if you are no longer obtaining water from the well the problem could be in the piping

- a disconnected or leaky well pipe
- a dirt or soil clog
- a check valve failure and clog

or in the well

- dropped water level, loss of artsian flow, or a fallen or failed well spool or seal inside the well

- or something else we've not thought of

Question: well pump shuts on and off

(Nov 3, 2014) Anonymous said:

pump runs for 5 min then stops for about 5 min

(Nov 20, 2014) Anonymous said:

my pump keep shuting off all the time can only get like 2 min of water at a time pump will kick on and then right back off

(Nov 21, 2014) Anonymous said:

pressure comes and goes not steady.

Reply:

Without more details we don't know that the behaviour you describe is abnormal

I would start with the diagnostics at WATER PUMP SHORT CYCLING found at the ARTICLE INDEX at CONTINUE READING .

Question: well pump won't pump water

(July 31, 2014) Henri Picard said:

Small well pump connected to river. Pump will not pump, so I changed the pressure switch. It still will not pump. But if I by-pass the pressure switch, the pump works perfectly, but will not stop of course.
Any idea what the problem is?

Reply:

Henri,

Your comment suggests that the pump and its wiring are OK, which leaves the pressure switch OR the ability of the switch to accurately sense system pressure. If you changed the switch and wired it correctly but it won't turn on the pump, and assuming you've checked for power, I suspect the switch is not sensing water pressure - e.g. if the mounting tube is clogged or the switch is not in the proper place.

Reader follow-up:

... thanks for your response. Not certain what you mean by "the switch is not in the proper place". I have changed the switch twice before and it has never been a problem. When I first replaced this last pressure switch; the pump would give me water for about 5 minutes and then the water pressure would drop to zero. If I then did not use the pump for a few hours; I could then get water but again for only 5 minutes. I checked the air pressure in the tank and it is 20 pounds.

Reply:

IF the switch worked in the location previously you're OK. Some installers might mount the pressure sensor too far from the pressure tank or on piping that can be turned off by control valves - interfering with its operation.

The latter part of your comment certainly suggests a very low flow well - recovering during the time you don't use it - in fact it sounds inadequate.

I add that

Some pressure control switches include a pump protection feature that will shut down the switch if the pump is drawing air. Some such switches have a manual re-set lever.

see
inspectapedia.com/plumbing/Pump_Protection_Switches.php

The fact that you've changed the switch twice suggests a systemic problem: switch burnups from short-cycling or dirt/debris clogging for example.

Reader follow-up:

From Henri, the pressure switch has a small metal lever on it's side to turn the switch on and off. it makes it easier to prime the pump when I put it in the river in the spring.

From your comment; "Some pressure control switches include a pump protection feature that will shut down the switch if the pump is drawing air. Some such switches have a manual re-set lever."

When I by-pass the switch, to pump works very well. Would it still do that if there was drawing air?

Thanks for being here because I live in the country and it is a long way to a water pump company and I would not want to have to pay for a service call.

I am not a mechanical type of person, but your comments made me think. I took off the small clear plastic hose that goes to the pressure switch; I took the fittings off and noticed rust. So I cleaned it up and the pump now works.
The only problem is that the pump come on every 5 seconds. It starts with good pressure but then diminishes for 5 seconds down to almost no pressure and then starts again. If I turned up the cut-off screw would that work? My pressure tank is a very small one, probably the smallest tank available.

Reply:

No Henri, you're quite right. If the pump were pumping air, that is not able to obtain water, it would misbehave regardless of the use of the pressure switch or direct-wiring to turn on the unit. If the pump provides water at good pressure when you omit the pressure control switch then we think the pump and wires to the pump are OK and we're back to the switch.

The small plastic hose that goes to the pump is how it senses water pressure. If your system is under pressure and you disconnect one end of the hose you ought to see water squirting out of the supply pipe. If you don't, either there's a valve closed or something is clogged.

Re Henri's last update - running pump but short cycling:

DO NOT try to fix that by changing the pressure switch cut-in/cut-out adjustment.

The problem is a short-cycling pump, caused by one of several possible problems (such as a waterlogged pressure tank or a piping leak) discussed in these two articles found in More Reading links TOPIC INDEX you will find

WATER PUMP SHORT CYCLING
WATER PUMP SHORT CYCLING CAUSE: WELL PIPE LEAKS

Reader follow-up:

(Aug 3, 2014) Henri Picard said:

Mr. Friedman, thank you so much for your comments. I am not mechanically minded and had no idea what to do to remedy my pump problem. But with your comments and direction I was able to read the articles you recommended, and after having read them many times, I was able to solve the short-cycle problem

 

Question: pump starts and stops at random times

9/6/14 Anonymous said:

My water stops in shower at sink or hose at random times and starts back after a min or 2. This has been going on for more then a year. The water may stop 2 times a day or twice a week just random

Reply:

Please see the diagnosis procedure at WATER PUMP INTERMITTENT CYCLING

Also see WATER PRESSURE PROBLEM DIAGNOSIS TABLE

Question: well short cycles but the tank pressure reads 50 psi

My well has been short cycling recently so I checked the tank pressure. It reads 50 psi. Wondering what is the cause. Could it still be waterlogged tank? - Chris 11/18/2011

Reply:

Chris:

indeed in a waterlogged tank the pressure will still go up to the cutoff point - but you'll see a very short drawdown time from when you turn on water in the building to when the pump has to turn back on - that's "short cycling" as we describe at WATER PUMP SHORT CYCLING CAUSES

Question: well pump loses pressure too quickly when water is taken from the system - drops in 10 seconds

My well pump seems to lose pressure (cut in?) too quickly when water is drawn from the well system. When the water is turned on the pressure drops from 60 PSI to 40 PSI within 10 seconds.

Once the system reaches 40 PSI the switch is activated & pressure is restored within a minute of the water being turned off. I believe that I have a tank with a bladder (it an Amtrol tank) & I've tested the pressure of the tank when the well system is active (it reads 38 PSI).

I've also tested the pressure after cutting the power to the system & draining the tank (0 PSI). I'm not sure why my tanks loses pressure so quickly & i'm afraid the well motor will burn out soon if this is not corrected. Is this an issue involving the thank bladder? Any advice? - Anon 3/5/2012

Reply:

Anon:

When the pressure drops rapidly as you describe it suggests that

- there was inadequate air in the pressure tank to deliver a larger quantity of water at higher pressure - that's then turning on your pump at 40

- there are other causes of sudden pressure drop seen right at the plumbing fixture, such as clogged house piping, but that wouldn't correlate with seeing the pressure fall at the tank and pump controls;

Take a look at the air charge level in your tank, or if it's a bladder type tank, look for a burst bladder.

Reader follow-up:

Thanks Joe,
I recharged my tank & everything seems to be working properly now. I also think I found the culprit that caused the pressure drop. After refilling the tank, I could hear a slight hiss coming from the Schrader valve.

I'm assuming this is a slow leak & is what caused the drop in pressure (I recently purchased the home where the well is located). Any ideas for correcting this issue? I'm going to research it now, but would like to avoid buying a new tank if possible. In the meantime, i guess my only fix it to monitor the tank pressure & recharge as needed.

Question: water pump turns on and off a lot, and water temperature in the shower then fluctuates

I have a water pump that seems to turn off and on a lot when we run water, especially in the shower.

When the pump turns on, our water temperatures fluctuate. We thought it was the water heater so we replaced that. Water temperatures appear better but the fluctuation is still there. We do have a leaking water hose connection outside of our home but just drips.

Could that explain the water pump running a lot? Since replacing our water heater we also lost some of our water pressure on the hot water, cold water is fine. Can you explain what could be causing the temperatures to fluctuate when the water pump turns on? Our water source is spring fed if that helps at all. Thanks! - Jennifer Beckler 10/3/2012

Reply:

Jennifer,

A dripping hose will cause the water pump to turn on intermittently but infrequently as a drip will take a long time, perhaps hours, before it alone can drop water pressure in the tank enough to turn on the pump (and that's assuming no other water is being run in the building).

However take a look at the gap between cut-in and cut-out pressures in your system. If that gap is too big, say more than 20 psi, at the low-pressure end of the cycle the incoming water into your hot water tank will be at lower pressure, thus the outgoing hot water will also be at a lower pressure; even though the cold pressure is also dropping correspondingly, that may affect the hot-cold mix so that you notice it in the shower.

If the gap is 20 psi or less then I wonder if there is a restriction or blockage in the hot water piping system - a flow restrictor or an accidental blockage such as a solder blob at a pipe connection or a valve partly closed. If so, the lower flow rate permitted through the blockage point will exaggerate the effect of the low-pressure end of the pump cycle.

Question: sanded the points in my pressure control swith

(Aug 9, 2012) Judy said:

My water pump pressure control switch I'm sure is bad. I cleaned the points with a little sand paper and cleaned out dirt and ants and it's working but still won't come on all the time. I use to be a car mechanic and not sure if you can just replace the points as if it was a distributor. Should I just replace the whole pressure pump switch? and does it come all together where I don't have to do anything with the new points in it. Do they come all together with new points and just replace the whole thing. Thank You. I will wait for a reply.

Reply:

Judy,

I would replace the whole pump pressure control switch assembly; that'll get past those burned sand-contaminated points that won't be long term reliable anyway once sanded, and also might discover and fix a clogged switch sensor port on the switch bottom. No I don't see replacement points - just the whole switch.

Question: how can adding air to the water tank stop the pump from turning the pump off?

(Aug 11, 2012) Murray said:

Hi,
I need some help with my house water pump.
I have a bladder-type cylinder.

Pressure switch was fine but I pumped a little air into the bladder today with a hand pump (it may have let more out than I added, do't know for sure) as I suspected it was getting low, and now the pump will not switch off, just keeps running and the pressure gets so high I need to turn the pump off at the power.
The pressure switch is one year old and I have not altered it at all, the only change is the amount of air in the bladder. I've now pumped the bladder to 25psi with a compressor.

I have no gauge on the pump but if I put a tyre gauge on the bladder valve it shows about 50psi and then does not go any higher. The gauge is a cheap tyre gauge so probably not accurate.

My question is, how can altering the pressure in the bladder (less or more) stop the pressure switch from turning the pump off? And what is the suggested next move (other than try to find a shop locally with a decent water pressure gauge on a Sunday!)

Also, is the air pressure in the bladder equal to the water pressure in the cylinder, ie if water pressure is 45psi does that mean the bladder pressure would also increase to exactly 45psi?

Thx
Murray

Reply:

Murray,

The air in the air bladder in a pressure tank would only get low if the tank had a leak. Inspect for rust perforations and try a bubble of soapy water or spit on the air valve to see if a leak is there.

Pump not switching off most often says the pump can't reach cutoff pressure, either because of low water supply in the well, a well piping leak, or a switch with cutoff set too high.

But the fact that your pressure gets very high tells me a different story.

Assuming you are seeing that high pressure at a guage on the system, it's possible that the pressure switch itself is NOT seeing that high pressure. That can happen because the sensor port on the switch base or the tube feeding water pressure to the switch or both have become clogged. Try changing the switch and the sensor/mounting tube or pipe nipple.

And set the air in the water tank bladder to a proper starting pressure with an empty tank.

Question: water pressure drops off very suddenly

(Aug 12, 2012) Lynn said:

So much information here - Thanks. We have a 1hp deep well jet pump. Not quite 3 years old. It had just started to short cycle - I am guessing from what I have read here. The water pressure tank seems fine. The piping, foot valve and all other parts are about 11 years old.

The problem we are experiencing is the pressure on the tank, when water is running, goes from 50psi steady to about 40, then plunges quickly to 20-25 before the pump kicks on. It does a hesitated start starts stops starts again to get back to 50. Would this be do to a leak, foot valve problem, or what?

Just trying to decide where to start next as time is not something we have to spare. Thanks for any information!

Reply:

Lynn
Usually a rapid pressure drop points to a water logged tank, easy to check,
But the hesitating start suggests a bad switch, perhaps the switch sensor port is dirt clogged.

Question: rapid cycling at end of pump cycle

(Aug 20, 2012) Ignacious said:

My pressure switch (brand new) kicks in @ 30psi just the way it should but rather than building to 50psi and shutting off it cycles (every 30 seconds or so)in short 2 lb bursts until it obtains 50psi - then shuts off. I can hear the water coming into the house from the pump with each cycle.

And, there's a buzz coming from the breaker in the electrical panel with each cycle. Ideas?

(Jan 1, 2013) Anton said:

I replaced my 1/2 HP, 10 GPM submersible pump a couple of weeks ago. I noticed the pressure switch was not working and replaced it. Pump and switch are working fine, however, when pump is cut off at 50 PSI, system pressure rapidly (5-10 secs) drops and pump kicks on again at 30 PSI. I've checked the pressure tank (28 PSI). Any thoughts on where I am losing pressure?

(Apr 2, 2013) andrew said:

just replaced the pressure switch 30/50 and it is short cycleing what did i do wrong

Reply:

Try lowering the cut-out pressure setting as your pump may be having trouble achieving that pressure - a sign of a damaged or worn pump or low voltage.

Question: problem with extreme pump short cycling

(Aug 22, 2012) ROCKY said:

I have a 300 ft deep well and two 30 gallon bladder tanks. I have been having a problem of EXTREME short cycling, once the pressure switch cuts in at 40 psi it will run and build pressure but most times before it gets to 50 psi it will short cycle on/off every 1/2 of a second sometimes

I have to reset the red button on the bottom of the well box where the run start capacitors are. I have changed out the pressure switch as well as the pump capacitor box and drained both bladder tanks of water and charged the air side to 38psi...what's left to check?

Dec 28, 2012) Jill said:

My pump motor cuts on for 1 second & then shuts off. I just replaced the pressure switch & gauge, thinking that was the problem. The tank pressure is set at 2lbs less than the cut-in pressure. The cut-in on the pressure switch is set at 38 and cut-out at 60.

When I turn on a faucet, the pump turns on and immediately reaches cut-out pressure and turns off. About 16 seconds later, it turns the motor on again for only 1 second. What can I do to keep the motor running longer than 1 second? I am afraid of burning up the pump motor with the frequent cycling.

Reply:

Usualy I find that a filter is clogged or a valve is closed between pump and pressure tank.

Question:

(Aug 26, 2012) nageshdobi said:

My borewell is 305 feet water what we got is 2& half inch when we start motor in the morning its fills 2500 ltr water within half hour & againg i switch off & on after 30 mins water will come only for 10 min with same pressure motor will be running

there is no water flow will be zero againg i leave 2 to 3 hrs & on the motor water will be filled what is the problem source is down or motor problem please let me as soon as possible

 

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