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.

On 2020-09-03 - by (mod) - what pump on-off frequency or interval is considered "short cycling"?

Greg

At 30 seconds or less intervals between pump on Cycles I consider that short cycling that should be addressed

On 2020-08-31 by Greg

A follow up question to my previous one. In general, at what frequency of turn on to turn on ((i.e., from when it clicks on at 40, pumps up to 65, drops back down to 40 and clicks on again) do you start to worry about burning out your well pump motor or your switch? Every 2 minutes? 5 minutes? Etc. Thanks so much.

On 2020-08-29 by Greg

I really appreciate your comments but am having a slight problem with terminology. Is the “cycle” of a well pump measured by the time from when it turns off to when it turns back on or the time from when it turns on until the time it turns on again? I have a bladder tank set at 40 psi/65 psi.

When I run three outside hoses it takes roughly a minute from when the pump shuts off at 65 until it turns on again at 40. It then takes about 4 minutes from when it turns on at 40 until it shuts off at 65, i.e., a total of five minutes between turn on’s. So is my cycle only one minute or is it 5 minutes? And in either case, does that sound like I’m likely burning out or shortening the life of my pump? Thanks much.

On 2020-06-25 - by (mod) -

Ed

It might be helpful to watch the pressure gauge when your pump is turning on and off. Either water is not getting into your pressure tank or there's a God that's closed on the outlet side of your pump.

I have a set of problems can be traced to a pressure control valve that's to re clogged and is not working properly

On 2020-06-22 by Ed

Even if I hook my pump up direct my pump only runs for 2 seconds and shuts off what happened

On 2019-02-14 by Thanks i will try this.

On 2019-02-14 by (mod) -

Possibly the tank bladder is stuck against the tank inlet and ban be freed by a brief higher oressure as long as you stay below the tsnks safe upper pressure limit.

On 2019-02-14 by Gloria

Just installed a new deep well water pump and new precharged bladder tank but pump is short cycling or kicking on and of again every few seconds. Can hear the pump turning the water used to prime it and both lines running to jet in well were profiled before hooking up the pump to lines . I am stumped as to what is causing this do you have any suggestions

On 2019-01-19 - by (mod) -

BV

In your photo the green handled valve appears to be a shutoff between well piping and the pressure tank and switch.

It's common for an old, seldom-used water valve to fail to work when needed. It can be replaced by a plumber.

Your description of conditions at the well sound like a flowing artesian well.

You will want to read details at ARTESIAN WELLS, WELL SPOOLS inspectapedia.com/water/Artesian_Well_Spools.php

Your concern about a short 40-second tank fill time was reasonable- in that ***IF*** also the draw-down time in water volume and time before the pump turned on was also vey short - that would be "short cycling" of the well pump, described at

WELL PUMP SHORT CYCLING inspectapedia.com/water/Short_Cycling_Pump.php

where we give causes and cures.

BUT your case, driven by a (at least sometimes) powerful voluntary water flow out of a flowing artesian well is a different situation. The water tank re-fills so quickly because your well is sending water up to the tank at an unusually fast rate.

The movement and "balloon" expanding sound you hear may be the rubber bladder inside your water pressure tank as it expands and contracts.

Above (for other readers) is the illustration you were attempting to attach

On 2019-01-19 by bvorobel@yahoo.com

Thanks so much for your information. You are the only one who made sense by writing in more layman terms.

I believe the large dial on the piping is a shut-off valve so you can stop the well water from coming into the house from the well. The plumber couldn't shut that down so I am assuming the artesian well water flow was still entering even though he turned the submersible well pump power off.
The well pump is 1/2 hp and the well is only about 100 feet deep when they hit the spring.

The outside water gate ("faucet") at the top of the well pipe (14 Inches above ground) flows continuously (ALWAYS) with an air space of about 3 inches into another pipe that flows underground to a creek

. I am assuming that would be enough water pressure to continue into the house on its own volition without power. That is why when the plumber was attempting to drain the basement water storage tank water just kept running out of it. Thanks again. I think I will leave well enough alone. I was concerned about the 40 sec it took to fill the tank as being too short of a time.

And that tapping the outside of the tank didn't offer two different sounds like one part (top) being a hollow sound as far as I can tell. Sometimes it seems like it an then again it doesn't. When it fills I can hear the movement of a balloon type sound or some type of movement. https://inspectapedia.com/water/Artesian_Flow_Disch_MI_050s.jpg

On 2019-01-19 - by (mod) -

BV

Thanks for an interesting question.

Certainly if you turn off power to the pump - as you indicated and as we see in the photo - then a flowing artesian well condition could continue to send water up to the pressure tank and building plumbing.

Some wells can temporarily function as a flowing artesian well (read about those by searching this site for ARTESIAN WELL) .

But "emptying 5 bucket of water" from a pressure tank isn't a decisive fact.

First: your water pressure tank is one that uses an internal bladder.

So there is NO reason that the tank should EVER need emptying. The bladder keeps water and air separated. Air doesn't get absorbed into water and air isn't lost from the tank unless the tank or its air valve or the internal bladder (one of those) is damaged or leaky.

The fact that your plumber was trying to empty an internal bladder pressure tank suggests inexperience or error.

If someone is trying to empty a tank like yours (which I said is not necessary nor useful) the air pressure in the water tank would make the tank continue to "empty" until pressure on the gauge and tank and system dropped to zero.

Your initial description of how your water system is operating does not sound odd to me except that the tank fills pretty quickly. That can be normal IF your submersible well pump is a powerful one and the well has great flow rate.

The tank air pre-charge of 28 psi is correct for a 30 psi CUT IN pressure control switch.

So in sum your system was probably working normally to start with.

Finally, you can rule out an "artesian well" as supplying water to your tank simply by turning off the valve (not shown , so I don't know if one is installed) between the supplying water line from the well and the tank itself.

but DO NOT do that if the pump is turned on as that could cause damage.

Turn off power to the pump

Close the valve

Drain the tank (for no reason as it's not necessary except for your own edification)

Notice that ultimately pressure measured at the tank drain or elsewhere in your home falls to zero and water stops leaving the tank.

At that point, IF you measured air pressure at the air pressure gauge on the tank top (under that little black cap on the right side of the tank top in your photo) you should see 28 psi of air pressure - that's the tank pre-charge pressure.

Close the tank drain.

Confirm the tank air pre-charge

Turn the pump on.

Done

On 2019-01-19 by bvorobel@yahoo.com

My well supply water tank is 33 gallon 30/50, tank PSI at 28. The more I read the more I am getting confused.

Pressure drops to the cycle on after funning faucets 2 minutes. When it is filling it takes 40 seconds to fill again. When water isn't used the pressure gauge is steady. So no leaks

. The plumber stated older style bladder pressure tank switch, drained and pressure check was all good. However, as he was draining it he emptied 5 buckets of water and the tank was still draining. Question is - is it possible that the artesian well with its constant flow of water could have been putting water into the tank even though the well pump power was switched off?

I believe that light switch is how to shut off the power to the well pump - right?
IMAGE LOST by older version of Clark Van Oyen’s useful Comments code - now fixed. Please re-post the image if you can. Sorry. Mod.

On 2018-12-03 - by (mod) -

Bill,

I would take a look in the ARTICLE INDEX found near the end of this article for our material on short cycling well pumps. That will address the on-off cycling of your water pump when the toilet is filling.

However well pump cycling would not in my experience change water temperature. So I suspect there's something else going on. Perhaps if you tell me how your hot water is made I can make a more specific suggestion.

On 2018-12-02 by Bill

When showering you get hot water and then cold water , keeps going back and forth every 5-10 sec. also when listening to toilet refill I can hear water system clicking off and on every 2-3 seconds, what is best guess for diagnosis

Question: normal well pump cycling times on and off

(Sept 14, 2012) M1helmethead said:

So I had a pressure tank installed on my well today because the system of short cycling bad. I would turn the water on and it would go up to 50 PSI and drop down to 30 PSI and repeat every few seconds. The tank I installed is a 20 Gal.

now when I run the water the pressure goes up to 50 in about 2 mins. and then down to 30 PSI in about the same time. Is this a normal rate?

or is there still a problem? I was under the impression this tank was suppose to keep that from happening.

Reply:

M1

You are describing what sounds normal for a small sized water pressure tank.

To get a water draw-down time that is longer there are two approaches - choose depending on your equpment's capability:

1. install a larger capacity water pressure tank - 20 gallons is not much drawdown, but you won't want to do this having just installed a new tank

2. adjust the pressure control switch to widen the gap between cut-in and cut-out pressures. Just be sure not to set the cut-out to a pressure higher than your pump can maintain. For example, if you set the cut-in DOWN to 20 or 25 psi and keep the cut-out at 50 you'll get a longer draw-down cycle.

The draw down time for a properly-charged water pressure tank (with proper air pre-charge) depends on tank size, water pressure, and the flow rate out of the tank.

Question:

(Sept 26, 2012) John said:

Hey guys, I have a 20/40 pressure pump with an internal bladder. When running a garden hose, the pump runs continously like it should. But when we have a shower, the pump runs for about 20 seconds (hits cut-out pressure) then shuts off, 20 seconds later it will fire up again.

This is only a problem because of the infinity gas water heater. The heater is programmed to heat the water at a certain rate but because the pressure & water flow changes, so does the temperature.

Meaning one minute the water is boiling then it goes luke warm. we have had the plumber sus out the water heater and it checks out, he says it is due to the pump shory-cycling. Any help or sergestions would be appreciated, John

Reply:

John that 20 second drawdown time sounds too short - I suspect the tank has lost its proper air charge or more likely the bladder is damaged and leaking; I'd first check out the tank for proper operation; Second you can install a flow rate regulator ahead of water coming into the water heater; a third step:

some of the pressure tank producers now offer a model that includes technology to smooth out the variation in water pressure delivered to the home due to pump cycling on and off - let me know if you need those details.

Question: proper pump air pre-charge pressure

(Nov 29, 2012) Jerry said:

pump runs short cycle recharge tank when drained water what should the pressure be and when filled what is its pressure to be for 40-60

Reply:

With an empty tank and pump off the air precharge should be set to 2 psi below the cut-in pressure

Question: intermittent pump troubles

(Dec 22, 2012) Francis Nwabueze said:

My water pump is a household 1.5hp surface pump. It has just developed a fault pumping intermittently.

I had changed all the valves and the problem seems not solved.I have checked if there is a loss circulation and the circulation appears ok. I Suspect water level has gone down and the is not getting much water to be delivered by the pump. What is your comment

Reply:

Francis please see INTERMITTENT WATER PUMP CYCLING

Question: hissing air leak sounds coming from the well

(Feb 17, 2014) sue said:

I can hear what sounds like a small air leak down in my shallow well and the pump will not run.I am wondering if I could have a bad foot value? We have just replaced the air tank,pressure switch and gauge.my well is only about 8 feet deep and has had a good supply of water for approximately 50 years.

please respond asap as I have been without water for 2 weeks and am very homesick.I'm on a fixed income and trying to figure all this out myself,with only help from a sister.

Reply:

Sue,

I'm of course not sure what you're hearing but:

Assuming you've got a one-line jet pump (which would work for a well just 8 feet deep) and the pump is above ground, with a simple foot valve at the bottom of your well pipe in the well,

THEN if you hear hissing I suspect that the pump is running but a leak at a pipe fitting connection or at a hole in well piping could be allowing air INTO the well piping;

Air in the line will cause air cavitation inside the pump body and the pump will run but not pick up water.

WATCH OUT: do not leave the pump running with no water - it can damage the pump.

As you just replaced the pressure tank I wonder: has your pump always been above ground? If so you can ignore my remarks below about snifter valves.

Start by using a good flashlight to look into the well casing: with the pump running you expect to see a single pipe in the well casing and from the above we expect to hear air entering the well pipe; but there might be something else going on.

Less likely, but you could be hearing air escaping from a bad snifter valve though I'd expect a snifter valve ONLY on a deep well with a submersible pump - search InspectApedia for "snifter valves" to read about that topic.

Question: Sudden water pressure surge to high pressure 80b psi

(Apr 26, 2014) Dave Jones said:

My water pressure suddenly went to 80 psi. It blew a water line. I’ve adjusted the pressure switch to 60-70 but cannot get it to drop below 60 psi. Is this due to a bad pressure switch? Thanks!

Reply:

David sometimes municipal water supply pressure varies quit a bit but if you have a pressure regulator installed and it is not keeping the pressure down to where you want to set it most likely the control needs to be replaced.

Question: short cycling pump traced to bad start capacitor

7/23/14 M.H. said:

my deep well submersible pump was short cycling, 4-5 seconds every minute or so. I changed the pressure switch but the problem continued. further troubleshooting revealed very high amp draw from the pump while it was trying to turn on.

The reason for this was the pump control start capacitor had burned out. The pump requires a "boost" of electrical energy to get started and run. When the capacitor goes bad, the pump is unable to start and run, causing a high amp draw and short cycling. replacing the start control box fixed the problem. Hope this helps.

Reply:

M.H.

Thanks for the comment.

Usually short cycling is caused by a waterlogged pressure tank.

But some pump motors use a start capacitor that can fail - just as you cite.

Or a pump motor may be old, worn, and have trouble starting - needing a stronger, booster start capacitor.

See inspectapedia.com/electric/Starting_Capacitors.php

But because a waterlogged pressure tank can cause short cycling that can in turn damage pump controls or starting capacitor, or the pump motor itself, I'd double check that the pressure tank is not itself waterlogged.

Question: sprinkler system pump short cycles

(July 30, 2014) Anonymous said:

just had new pump and switch installed for my sprinkler system. Pumps runs for while then goes into on/off mode of about 15 - 20 seconds. Am also starting to get sand build-up in the pump resovior. What do I need to do??

Reply:

Try the diagnostic list at WATER PUMP SHORT CYCLING DIAGNOSIS TABLE

Question: spring water, no pressure

(Sept 7, 2014) Corey said:

Hi I get water from a spring i have been doing this for 5 yrs now and been buying a pump per year due to gravel eating them up then they run but won't build pressure ! So I bought a bigger 1hp shallow well and put a whole house filter between foot valve and water pump will this work ? Or is there something else I need to do with this ?

Reply:

Corey,

A better solution is to build a spring house or box that accumulates a reservoir of clear clean water, protected from surface runoff, and deep enough that you can use a foot valve or strainer to keep dirt, gravel, debris out of the pump.

Question:

(Sept 12, 2014) Kathie said:

one miniute i have water and a little while later there is no water what causes this

Reply:

Kathie

In the page end ARTICLE INDEX either of these articles should help you with diagnostics

WATER PRESSURE LOSS DIAGNOSIS & REPAIR

WATER PRESSURE PROBLEM DIAGNOSIS TABLE

Question: short cycling farm well pump

Our farm well pump is short cycling when the water is run.

A constant pulse or surge.

It is supposed to cut in at 30 psi and cut out at 50 psi. However, the system shows 110 psi at the gauge. Turn the water on and it quickly drops to 80 psi where the pump cuts in and pegs the gauge, pulses between the peg and 100 psi until you shut off the water. Then it short cycles and settles at 110 psi. Although gauge shows 110 psi, water pressure appears normal..not 110 psi. I'm stumped.

Water pressure gauge shows 110 but I know pressure is not that high.

Also, the short cycling is a pulse or surge with constant clicking of the relay.

Reply:

Monte, this sounds like classic short cycling due to a water-logged tank and probably a debris clogged pressure gauge.

Try the diagnostic list at WATER PUMP SHORT CYCLING DIAGNOSIS TABLE

Monte replies: We also found that the pump starting capacitor seems to be corroded and leaking dielectric.

Reply: sounds like the pump needs repairs to start and run normally.

Monte Myers follow-up:

Dan,
The gauge face was bent causing the dial to spin on its' shaft. It wasn't clogged. I installed a new gauge. The tank had lost its' air. I added air and the short cycling stopped. However,I couldn't find any cause for the air loss.

REply:

Thanks for the update Monte. Air may be lost from a pressure tank by absorption into the water passing through if the tank is *not* one that uses an internal bladder to keep water and air charge separate. Air can also leak out through a pinhole leak in a tank or from a leaky air fill valve.

Question:

(Oct 20, 2014) yanna said:

My pump turn on and after 3sec the pump stopped and run again and stop again,,how to fix it

(Oct 29, 2014) Jackie said:

My pump stays on longer than it used to...is this short cycling?

Reply:

Jackie long pump on cycle says the pump can't reach cut-off pressure - this is not short cycling, but long cycling - perhgaps low water level in the well or a damaged pump or pressure switch set too high.

Question: wierd gauge pressure readings

(Oct 29, 2014) Anonymous said:

my guage goes to 50 drops to 10 water comes on and then at 50 pump stops and losw water pressure then goes down to 10 and repeats

Reply:

Sounds as if either water is running or there is a significant pipe leak somewhere, or perhaps a totally failed foot valve.

Question: hot pump motor, no water

(Oct 31, 2014) Anonymous said:

I have a water pump that I don't use often. Today when I turned the water on I did not have any.

I check the pump and the motor felt warm to the touch. I disconnected the power supply and turned the shaft. I plugged it back up and it eventually started back pumping. It stopped again and I replaced the pressure switch. It worked fine for several hours but now I have not water and the pump is not cutting on again. What could be the cause of this?

Reply:

Anon
Sounds as if the motor is seizing; you might try checking for lubrication requirements or for an impeller that is debris clogged. IF the pump is removed and disconnected from power and the motor won't turn freely, replace it.

Question: water pressure problems in Peru

(Nov 14, 2014) Anonymous said:

Hello vi am John Bickerton and live in Peru.
i have a problem with the pressure in my System and it is making a lot of pipes leak. When the Pump starts the pressure shoots up to 5 bar and is designed to run at 1 bar. Can you tell me how to reduce the pressure. it is a fairly new system
Help please
john

Reply:

Juan

Your pressure control switch may be improperly set, the pump may be over-sized, or you may need to install a pressure regulator on the house piping or at the pump outlet.

Question:

(Nov 16, 2014) greg lehman said:

twice this last weekend the water almost completely stooped flowing in the house . and then about 10 seca later started back up- there was also light sediment in the toilets when we got to the house and the aerators in the shower heads and faucets had small silt in them - pressure tank was about 70 lbs -any thoughts?

(Nov 26, 2014) Anonymous said:

why would my water pressure tank have no water in it?

(Nov 28, 2014) Paul said:

I have a issue with my switch short cycling , we replaced the pump, the water tank and the switch... ...for a few weeks, no issues, then it was short cycling so I just adjusted the pressure and it cleared up for a few weeks... ...but is now short cycling again, bouncing like a rabbit and not even reaching the 60lbs it should... ...what's next. I am so frustrated after spending a small fortune.

Reply:

Usually when a pump is switching on and off too often it's one of the causes at WATER PUMP SHORT CYCLING CAUSES - such as a waterlogged tank. If you are dead sure the water tank is not waterlogged then check for a debris-clogged sensor port on the switch OR a blockage in the water output such as a dirty filter.

Question:

(Nov 28, 2014) Anonymous said:

...there is no pre-filter, the tank is not waterlogged... ...have replaced the switch and checked the stem into the switch, no problem there.

(Nov 28, 2014) Paul said:

...so, I was thinking the issue may have been the charge in the tank (even though I had checked it when purchased and rechecked it)... ...there was over 50lbs of pressure in the tank so I let off all but around 40 just out of precaution... ...seems to have solved the problem.

...the irony here is, the comments on Lowes ad online pointed to cautions on the pre-charge, most of which were under-charged, mine was over charged then and I set it correct as I have read many times prior to putting this all in.

...I am starting to understand why plumbers charge the rates they do... ...I went into the wrong line of work.

...thanks for the help, DanJoeFriedman... ...I will be passing along this link to others.

Reply:

Paul the pre-charge in an internal bladder tank is indeed usually set 2 psi below the cut-in. If the bladder is ruptured, for example, then the tank becomes waterlogged.

Question: pump short cycles but pressure tank does not seem water-logged

12/11/2014 Ron said:

I have a Well Rite WR60 tank in my house system that was completely overhauled 4 years ago.
I'm experiencing short cycles and an extreme drop in pressure just as the pump is about to kick in at 40 psi.

First I replaced the 40 - 60 switch and no luck.

Then I checked the tank air pressure when drained and it was high - close to 50 psi.

Reset the air pressure to 38 psi and thing ran OK for about a week and then back to the short cycling and surging at cut in.

I've reset the air pressure several times but it never seems to last more than 4/5 days.

One thing that confuses me is that when I relieve the excess pressure there is no water coming out.
For what it's worth the tank is still under 5 year warranty but - probably pro rated ?
Thanks

Reply:

Ron

Have you checked for a pressure switch that is not sensing water pressure due to clogging due not to the switch(which you replaced) but due to a clog in the small diameter tubing on which either the switch mounts or that conducts pressure to the switch sensing port?

High air pressure in the tank after it's drained: could be a small leak in a tank bladder - in odd cases water leaks out of the bladder into the air space enough to keep pressure there abnormally high. If you think the tank is "empty" of water but it still feels heavy it may contain water.

I know we expect water to squirt out of the air valve when a tank is fully waterlogged, but it is possible for some water to be in the tank bottom but air still at the tank top (the water should be in the bladder not outside it in most designs).

I think of this as described by a few other readers as "pinhole leak in water tank bladder results in abnormally high air pressure creeping up in the pressure tank"

See PINHOLE LEAKS in WATER TANK BLADDER

Keep us posted.

Ron said:

I have a Well Rite WR60 tank in my house system that was completely overhauled 4 years ago.
I'm experiencing short cycles and an extreme drop in pressure just as the pump is about to kick in at 40 psi.

First I replaced the 40 - 60 switch and no luck.
Then I checked the tank air pressure when drained and it was high - close to 50 psi.

Reset the air pressure to 38 psi and thing ran OK for about a week and then back to the short cycling and surging at cut in.
I've reset the air pressure several times but it never seems to last more than 4/5 days.

One thing that confuses me is that when I relieve the excess pressure there is no water coming out.
For what it's worth the tank is still under 5 year warranty but - probably pro rated ?
Thanks

Reply:

Ron

Have you checked for a pressure switch that is not sensing water pressure due to clogging due not to the switch(which you replaced) but due to a clog in the small diameter tubing on which either the switch mounts or that conducts pressure to the switch sensing port?

High air pressure in the tank after it's drained: could be a small leak in a tank bladder - in odd cases water leaks out of the bladder into the air space enough to keep pressure there abnormally high. If you think the tank is "empty" of water but it still feels heavy it may contain water.

I know we expect water to squirt out of the air valve when a tank is fully waterlogged, but it is possible for some water to be in the tank bottom but air still at the tank top (the water should be in the bladder not outside it in most designs).

I think of this as described by a few other readers as "pinhole leak in water tank bladder results in abnormally high air pressure creeping up in the pressure tank"

Question:

(Dec 26, 2014) Mike Wells said:
I keep having to tap the control box to activate the pump. Everything works fine for most of a day, then the pump won't start unless I tap the control box. I have replaced the control switch in the box in the last month. In the control box for my pump there are two capacitors.

What is their purpose? Do they assist in the activation of the control switch? One may be faulty. The pressure switch is usually activated (I can see it is closed), but the control switch seems to need help activating sometimes.

Reply:

Mike

In my experience when tapping the pressure switch activates it I need to look for either a debris-clogged sensor tube or port or burned contacts. The capacitors in the higher-amperage or voltage control box for a well pump are probably a start/run capacitor for the pump. These are solid state but might be behaving oddly if there is a loose or corroded electrical connection. If I were shotgunning this repair I would

1. check or re-make all of the electrical connections in the control box

2. replace capacitors (cheap, easy)

3. Look for a bad relay and check for burned contacts or switches

(Jan 5, 2015) Mike Wells said:
Replaced the control switch. The contacts were all but burned off. Seems to be working.

Reply:

Sounds right Mike.

Watch however for short-cycling of the pump: a condition that can cause burned contacts.

Question:

(Feb 6, 2015) Anonymous said:
sometimes when my shallow well pump turns on and 30lbs it will not pump up i have release all the pressure from the tank and then it will prime itself and it will pump back why please

Reply:

See WATER PUMP DIAGNOSTIC TABLE

Question: pump cycles for no reason

My pump seems to run on cycles even when we're not using water.

Reply:

Kevin

I'd start by looking for a leak in the building or well piping. Turn off water into the building: if the cycling continues the leak is on the well side.

Question: pump turns on and off several times before stopping, then pressure holds.

(Apr 5, 2015) Jim said:
well pump pressure switch set at 20 on 40 off keeps turning on an off for 4 to 6 times then holding pressure

Reply:

Jim typically I see this when

- the pump is having trouble reaching the cut-off pressure due to pump damage, a leak, running water, or a defective pressure switch

Question:

(Apr 4, 2015) dave m. said:
this site has got to be the most complete and easist site i have ever used thank ypu so much for all this valuable info. dave m.

Reply:

Thanks so much Dave for the nice comment. We work very hard to provide useful information - so your comment is really encouraging.

Question:

(June 7, 2015) carolyn said:
Should my pump kick on and off when using water? Or should it run the entire time the water is being used? Ty

Reply:

Carolyn:

If water is being run faster than the pump can deliver it from the well then the pump will run continuously.

Question:

(June 8, 2015) Anonymous said:
problem with water turning off sometimes (daily) and restarts a minute later or maybe 10 minutes later. have already tried replacing pressure switch.
M Johnson

Reply:

Anon

WATER PUMP SHORT CYCLING CAUSES

should help you out.

Question:

(June 15, 2015) short cycle said:

I just changed my bladder tank with the same size that what there before, i set the air to the required -2 so 18 because 20/40. pressure gauge shows 40 and when the pump is on it reads 40. Now the pump turns on about every 2 minutes and surges with NO water running. There is nothing dripping or leaking and not sure what I am missing. Any help would be helpful. Thank you

Reply:

Short

It sounds to me as if there is a leak or water running or a bad foot valve or check valve. Your leak could be back into the well or anywhere in the well piping system

Question: more help for short cycling pumps: diagnosis & repair

19 August 2015 Sandra said:

I spoke with you (I think) about my pump short cycling. Short review. Pump began short cycling about 5 days before water stoppage. Turned running water off and didn't give it enough time and when I checked the water it stopped within the first minute or so. I keep forgetting to stop by the auto parts place to pick up an air gauge.

I wanted to see if there was air in the tank at empty so I took a screwdriver out to open the air valve. Before I did that I shook the tank and it was empty.

I left a short burst of air out of the tank after which the pump turned on in a short cycle and turned right back off. I noticed a very low hum coming from the box that sits atop the pipe coming up out of the ground. I hit it with my hand and it faultered a little but went back to the hum.

So I hit it harder with my fist and it stopped and didn't start the hum again. Shortly after that the pump came on and ran a considerably longer time than the short cycle and the tank now had a good amount of water in it as I could no longer shake it.

I then turned on a hose and let it run full force and the pump didn't turn on right away and do the short cycle as it had been doing. When it did turn on it ran for a more normal time and then cut off. There has been no further short cycling but I am afraid to leave it on so I have it turned off at the breaker in the house. Now my question is, it's a submersable pump, what is in that silver box atop the pipe that could stick or cause short cycling?

Reply: bad pressur switch?

Sounds like a bad pressure control switch or a sometimes- or intermittently-seized pump motor.

I'm not sure what silver box you mean, nor where it is. Some submersible pumps use both a pressure control switch and a heavy duty relay switch. The pressure switch turns on the relay that turns on the pump.

19 August 2015 Sandra said:

Wouldn't I have no water at all if the pump motor were seized? After I hit the box (looks like some kind of control box) the pump began working normally with good pressure. Now the pressure gauge is reading "0" but I don't know if that is an accurate reading, it was replaced two years ago along with the pump.

I didn't try hitting it, lol. I would imagine that you would recommend changing that out too? I'm really nervous around electricity so I didn't open the "box" that humming, I just wacked it a good one. It's about the size of a piece of paper 8" x 5"ish as I didn't measure it that's an estimate of the size but it's not the little one that houses the points.

I am making a special trip to the auto parts place to pick up an air gauge. I would also like to thank you for being available like this to ask questions of. You have certainly helped a lot of people by doing this.

Reply: whack-a-mole water pump repair methods

Sandra

Yes if the pump is seized it won't pump; though a damaged impeller or low voltage or a blockage or leak in well piping can cause a reduction without total cessation in water delivery.

Hitting the parts to make them run suggests that the pressure sensor port on the pressure switch or the tube that conducts water pressure to it may be clogged.

Whackamole is satisfying but it's not a durable repair.

20 August 2015 Sandra said:

Finally got an air gauge. the pressure in the tank with the power on is 46.It has not short cycled since it began to work again. Now what do I do?

Reply:

I don't know what "46" means. The pressure in your water system will change constantly as water is run and as the pump cycles. You want the air pressure to be set at 2 psi below the pump cut in pressure.

If the pump is only intermittently short-cycling the problem could still be at the pressure switch: debris clogging, burned contacts, or at the water tank if an internal tank bladder sometimes does not accept water into the tank. Also look for water that has been running somewhere in or at the building.

22 August 2015 Sandra said:
Well, I have another stupid question for you then. How do I know the cut in pressure of the pump? and the 46 was the air pressure in the tank while there was power to the pump but the pump was not running and there was no water use.

Sorry that pressure was from a tire air pressure gauge.

Reply:

The "CUT IN" pressure is the pressure read on a pressure gauge when, as water is being run in the building the fall in system pressure causes the switch to turn on the pump.

No individual water pressure number (suich as your 48 psi) can be interpreted clearly unless we know where we are in the pump cycle.

For example:3
Water run, pressure falls to 30 psi, pump turns on, water is turned off, pump continues to run until water reaches 50 psi.

Pump turns off. Someone tuns a small amount of water dropping the pressure to 40 psi then turns the water off. Because pressure has not reached the cut-on pressure (say 30 psi) the pump doesn't run.

23 August 2015 Sandra said:

Can that pressure, the "cut in" be measured with the water running and using the tire air pressure gauge to check the air in the tank? Or do I need to go buy a new gauge that goes on the pipe coming out of the tank? It seems to be frozen at "0"

I know some of the questions I ask are rather dumb. I'm not used to doing these types of things, my husband used to do them. You know fix the pump, work on the cars, I took care of the house and garden. Anyway I just wanted to thank you for your patience with me.

I just don't have the money right now to call in someone unless it's something I absolutely have to do.

Reply:

Sandra:

well sort-of; when water is running you cannot get a very accurate pressure measurement as pressure in the system will be varying; but you can get close if you are monitoring pressure and get a reading right at the moment that the pump cuts in.

Easier is to watch the installed pressure gauge right at the pump system while water is running.

Your questions are always welcome: working together makes us smarter.

25 August 2015 Sandra said:

I believe then my best option will be to buy a new gauge and install that. I assume I will do that with an empty tank. I have had no further problems with the pump short cycling, I have not opened the humming box, but, what is the chance something got into that box, and when I hit the box it knocked it loose?

I think, when the pump burned out 5 years ago, that I was told they found a rather large lizard that was lying on the switch, and my neighbor told me his father once had problems with his pump and when checked it was filled to the top with roach droppings. I do live in a rural area and it is a wooded area close to the tank.

Reply:

Keep in mind that the gauge is only giving information; the pressure gauge itself has nothing to do with when the pump turns on and off.

Question: can I turn water off to diagnose a short cycling well pump?

21 August 2015 char said:
If your pump cycles every 9 or10 min can I turn water to house off if it still cycles to often then the leak is not in house?

Reply:

Exactly right, Char. If you turn off the water supply into the building at the pressure tank and if the pump keeps cycling on and off then we know that the problem is at the pressure tank, pressure switch, or in the well piping, such as a leak in well piping, a leaky foot valve, etc.

Question: pump runs intermittently

(Jan 21, 2015) Ray said:

My pump (from tank to house) has been running intermittently and actually shut down twice in the last 24 hours. I went to the pressure switch and was able to manually restart the motor twice, once last night and once this morning. It happened a third time this morning and I was unable to restart it.

When I try the manual restart the switch sparks and then I hear only a hum rather than the pump kicking on.

I replaced the pressure switch because the contacts looked burned. Still no pump start. I also cleaned out the filter and checked the pressure in the bladder tank.

Pressure was very low so I added air up to 25 psi but still have no pump start. Pump is at leat 10 years old. What next?

Reply:

Ray

This sounds like there is a leak somewhere, perhaps a bad foot valve, a leak in well piping, or water running somewhere - that is exhausting water in the well. If the pump no longer starts it may have been damaged by running dry. Start by checking for power, reset switches, etc. to be sure the pump gets power.

If you added enough air pressure to put the tank pressure above the pump cut-in pressure, of course, it'll never start.

See WATER PUMP INTERMITTENT CYCLING

Older Short Cycling Well Pump Diagnostic Table FAQs

On 2014-02-14 by (mod) - signs of a clogged pressure control switch

Sounds as if the pressure switch is not sensing pressure properly so turning the pump on late. Try replacing the switch and its sensor tubing

On 2014-02-14 by Bill Bishop

We have a well that supplies our house. Just recently I turned on the cold water and the pressure was very low and a few 5-10 seconds later the presure picked up to normal,only to repeat the process again.

This problem strted a few days ago and has not changed. It does the same thing on hot. Does anyone have any ideas to what could be wrong?

On 2013-04-01 by (mod) - Declining pressure during the pumping cycle sounds like a well running out of water.

Anon,

Declining pressure during the pumping cycle sounds like a well running out of water.

On 2013-03-30 by Anonymous

Forgot to tell you that the pressure tank and the pump are both new. Just replaced sence OCT.

On 2013-03-30 by Anonymous

I have a well that starts to turn on and off when I am trying to fill the horse water tub.. The water will come out with a lot of pressure and then less and less until it stops. The pump starts to cycle on and off. The water will eventually. I will turn the water off and in a few minutes the water will come out again.

The really strange part is it doesn't its prime. The well well is less than 25 feet deep. Any ideas why this happens?

On 2012-04-06 by albert bonneveld

Don't know how the plastic tube can be cleaned

On 2011-10-07 by (mod) - "Clicking" suggests to me that your pump is in the well - and that you're just hearing the relay switch that turns the pump on or off?

"Clicking" suggests to me that your pump is in the well - and that you're just hearing the relay switch that turns the pump on or off?

In any case, if the relay is trying to turn on the pump that means you have power. If the pump is visible and not starting, I suspect a wiring problem or a burned-up pump motor or seized pump.

If the pump is a submersible, in the well, I'd expect your well driller/plumber to do a few above ground electrical tests before pulling the pump to repair or replace the pump, foot valve, or other problem.

"Short cycling" as we use it here, means that the pump is turning on and off too often, but nevertheless is delivering water.

On 2011-10-07 by Kim Cleveland

We just bought a 15 year house with a well that takes care of faucets on the outside of the house only. After reading this article, I think the well was short cycling. It kept clicking. Now it doesn't even turn on. Is there anything that I can try before I call someone out to look at it?

On 2011-08-24 by (mod) - should water pump cut off and on while running sprinkler system

Earl: it depends ...

If the rate at which water is being run out of a building plumbing system is LESS than the rate at which the well pump can deliver water to and restore pressure in the pressure tank, then it would be normal for the pump to turn on and off at intervals all during the time the water is being run.

If the rate at which water is being run out of building plumbing is GREATER than the maximum rate at which the well pump can deliver water to the system then the pump will run continuously until water being used is shut off. At that point the pump will continue to run until the pressure control switch "cut-out" pressure is reached.

For a given, fixed water usage rate, the actual behavior of a well pump at a property might also vary seasonally depending on variations in the well recovery rate or flow rate.

Some well systems include equipment that will reduce the output of the pump so that it never exceeds the recovery rate of the well itself - that's a step taken to avoid damaging the pump.

On 2011-08-24 by Earl

should water pump cut off and on while running sprinkler system or stay on all the time. running 8 heads per zone.

On 2011-08-15 by (mod) - drain all the water from bladder type pressure tank to reset air pressure in tank

Tom, in a bladder-type pressure tank, because the bladder keeps water and air separate, you should not normally have to RE-set the tank air pressure.

If the bladder is intact and the air pressure needs to be changed you can do so, however, through the tank air valve (schrader valve) without draining any water though if you turn off the pump and run water until the pressure is removed from the tank it's easier to know where you are in the pressure adjustment process.

You will want to read
WATER TANK BLADDER PRESSURE ADJUSTMENT in our ARTICLE INDEX

On 2011-08-14 by tom

do you have to drain all the water from bladder type pressure tank to reset air pressure in tank

On 2011-08-09 by (mod) -

You're quite right, Anon./ Larry

I think we started with the guess that it was a bad sprinkler head or broken underground connection. That's what we found in a similar case in Tucson recently.

On 2011-08-09 by Anonymous

Dan, the pump is two years old and very well maintained. Wouldn't the pressure switch affect the other three stations? They work fine. It is just the one station that causes short cycling. I tried lowering and raising the flow on that particular valve to fine tune the flow.

As expected, the lower settings cause quickening of the short cycle frequency. Wide open the pressure appears normal but the short cycling happens within ten seconds of activating the station shutting on and off a few seconds apart. I am planning to dig up that entire area anyway.

Making landscape design changes. Hope to find something in the piping.

BTW, I inherited this system from person who cut a bunch of corners in the design and quality of materials. Every new watering season little things go awry causing much frustration. Time to rip 'er out and start fresh anew. Thanks for your help and guidance.

On 2011-08-06 by (mod) - 1 lawn watering station won't work

Larry when I have seen some lawn watering stations working and one or more not, I have traced the problem to damaged sprinkler heads or piping, not the pump itself.

But the short cycling you describe sounds like either a blockage in the pump output piping or a water tank that has lost its air charge, or less often, a bad pressure switch.

On 2011-08-06 by Larry G

I have a shallow well above ground pump. There are 4 active stations for watering the lawn.

All the stations work great except for one. It comes on with good force but about 15 seconds into watering, the pump begins to short cycle. I've tried adding more sprinklers and subtracting sprinklers. The other three stations work as they should. Please advise and thanks.

On 2011-07-22 by (mod) - well pump is constantly cycling with no known water being used

Mark: when a well pump is running unexpectedly one of the first things we do is turn OFF all water entering the building by closing the water valve outlet from the pressure tank.

That step will eliminate hidden indoor running water that you've missed, like running toilets or a hidden supply pipe leak.

Now if the pump still cycles on and off then we probably have a leak in the well piping between the building and the well. That can be a hole in a pipe or a bad check valve or foot valve.

On 2011-07-22 by Mark L.

Additional information: The pressure switch is actually set to a low of 30 psi with a high of 60 psi. I timed the pressure changes and the pressure increase from low to high takes between 5 and 7 seconds with the slow drop back down taking about 2 and 1/2 minutes. Again, thank you for any advice you can provide.

- - Mark

"swith" = "switch" below. :-)

Our well pump is constantly cycling with no known water being used in the house, barn or irrigation system.

When the pressure gauge reaches 40 psi the pump kicks on and the control box makes a new rattling sound (in addition to the "normal" sound of the well pump being turned on).

The pressure gauge moves very rapidly from 40 psi up to 60 psi and the well shuts off. There is no rattle at the shut off point.

The pressure then drops slowly down to 40 within a matter of minutes (didn't have the chance to actually time it but you can see it moving) and the cycle repeats.

The pump and all in-ground components are, AFAIK, original to the house, which was built in 1989. The control box is also original.

The pressure tank was replaced about 7 years ago and the pressure swith was replaced about 5 years ago. Thanks in advance for any guidance you can provide. Mark

On 2011-07-19 by MIke

Thanks for the advice. I think the pump will have to be pulled.

On 2011-07-19 by (mod) - explanations for poor water supply for the irrigation system.

Mike:
From outside the well and pump system I'm not sure either how we'd decide between your two possible explanations for poor water supply for the irrigation system.

Start by looking into the well and measuring the distance to the top of the water and to the bottom of the well to get the static head data. If this water volume is changed from what it was historically then the well water table has fallen.

Second if the pump is running look into the well for the draw-down of the water top level; if the pump runs and the water is not moving down in the well casing the pump is not pumping water.

If you cannot see or measure (string, float etc) the water levels in the well you're left with these next steps:

You might check the amperage draw of the pump to look for a bad motor but that won't tell you if an internal pump part has failed and thus reduces the amount of water moved by the pump.

I think you have to pull the pump and inspect and test it above ground or try a temporary replacement pump back in the well; once you know there is a good pump in well you can test the well draw-down cycle or the well recovery rate.

On 2011-07-17 by MIke

I have a submersible pump and a holding tank for irrigation. The pump cycles for about 15 minutes then shuts off repeatedly taking 12 + hours to fill the tank. How do I know if I have a pump problem or a low water table?

On 2011-06-16 by (mod) - leaky check valve that allowed the whole pipe between well and house to fill with air

Sorry Heather that I could not reply immediately; I'm sure by now you had to find a plumber to fix the system since no one is going to live with no water for 3 days or more. Your note sounds as if your pump was not maintaining prime, perhaps because of a leaky check valve that allowed the whole pipe between well and house to fill with air. Sometimes we can get by a big air problem by priming the pump several times, but ultimately you'll want to find and fix what may be a bad check valve or a leaky well pipe.

Of course a well could have suddenly run dry (perhaps when a neighbor drills a new well that taps into your aquifer, but that's less likely.

Let us know what you found - it will help other readers.

On 2011-06-13 by Heather

We went on vacation last week and came home to no water. We checked the pump and it would prime up for a few minutes and run water (lots of air bursting out) and then the pump would lose pressure and no longer produce water. Does that mean the well is dry or is that a faulty pump? The pump is less than 2 years old and we have had no other problems until now.

On 2011-05-20 by (mod) - If your well pump is cycling at night when no one in the home is running water,

If your well pump is cycling at night when no one in the home is running water, there is a leak that needs to be found and fixed.

It could be due to something as simple as a running toilet or something more hidden such as a failed check valve or a leak in well piping. I'd focus on finding and diagnosing the problem first, before trying any more costly or complex solutions that may, ultimately have been focusing on the wrong thing.

If you are dead sure that the problem is well piping between house and well, not a check valve, for example, then that leak needs to be found and the leaky piping section replaced.

You cannot normally just swap the two lines leading down into the well. What you describe is a two-line jet pump. That system works by forcing water down into the well where it squirts "up" through a venturi that creates a larger up-flow of water back through the second well line into the water pressure tank and into the building.

Even if you swapped the two lines at the well head so that the venturi continued to work properly, you still have a leak in the well piping. Your idea of "fixing" the leak by feeding a smaller diameter pipe through the existing lines might indeed get around the leak, but you'll also reduce the water flow rate.

Before making such a change I'd ask the pump manufacturer to confirm that it's acceptable to use the smaller diameter piping.

On 2011-05-16 by Brian Amyotte

I recently noticed my pump is cycling with no water draw in the house. At night time last week it would cycle about once an hour now it is every 45 minutes. Yesterday I replaced the line from the top of the well and the foot valve and it still is cycling.

I have already isolated the house so there are no leaks within the house. I am sure that the leak is between the pump and the top of the well. There are two 1" poly lines running from the pump area to the top of the well.

12 years ago I had a problem and switched from one line to the other. My jet pump uses one 1" line to draw. The existing lines are buried under concrete and are not accessible. What I am thinking of doing is to use the existing two 1" lines as a sleeve and feed 3/4" poly lines thru them from the pump to the well.

At each end I would make up a fitting that would join them up and back up to the 1" size I need for connecting the pump to the well. Does anyone see a problem in doing this?

...

Continue reading at SHORT CYCLING WATER PUMP - topic home, the home page for this water pump topic, or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see these

Recommended Articles

• WATER PUMP INTERMITTENT CYCLING - pump runs when no water is being used
• WATER PUMP SHORT CYCLING - home
  • WATER PUMP PRESSURE CONTROL SWITCH CHATTER
  • WATER PUMP SHORT CYCLING CAUSES
  • WATER PUMP SHORT CYCLING DIAGNOSIS TABLE
  • WATER PUMP SHORT CYCLING - PIPE LEAK
  • WATER PUMP SHORT CYCLE STOP VALVE

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