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WATER PUMPS, TANKS, TESTS, WELLS, REPAIRS
WATER CONTAMINANT LEVELS
WATER HAMMER NOISE DIAGNOSE & CURE
WATER ODORS, CAUSE CURE
WATER PUMP REPAIR GUIDE
WATER PRESSURE LOSS DIAGNOSIS & REPAIR
WATER PUMP SHORT CYCLING
WATER SOFTENERS & CONDITIONERS
WATER TANK REPAIR PROCEDURES
WATER TANK: USES, TROUBLESHOOTING
WATER TESTS, CONTAMINANTS, TREATMENT
WATER TREATMENT EQUIPMENT CHOICES
WELLS CISTERNS & SPRINGS
WELL FLOW RATE
WELL WATER PRESSURE DIAGNOSIS
WELL YIELD IMPROVEMENT
WINTERIZE A BUILDING
Internal bladder water tank troubleshooting: this article describes the diagnosis and repair of internal bladder type water pressure tanks: how they work, what goes wrong, how to fix it. We explain how internal bladder type water pressure tanks work, what goes wrong, how to diagnose the trouble, and how to repair it.
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Our complete list of internal-bladder type water tank diagnosis & repair articles is at the end of this page.
Readers of this document should also see WATER TANK BLADDER PRESSURE ADJUSTMENT where we describe adjusting air pressure in a bladder type water tank to factory specs, and also see Water pump and pressure tank repair diagnosis & cost an specific case which offers an example of diagnosis of loss of water pressure, loss of water, and analyzes the actual repair cost. The illustration at page top is courtesy of Carson Dunlop Associates.
What's the Difference Between a Bladder Type Captive Air Water Tank and a Conventional Steel Bladderless Water Tank
Bladder Type Captive Air Water Tanks
Traditional no-bladder Steel or Fiberglass Water Tanks
Diagnosis of a burst water tank bladder: if you remove the cap from the air valve on the top of your water tank and momentarily depress the pin in the center of the schrader valve, normally air will hiss out.
Watch out: Don't keep holding this valve pin down or you'll lose the air charge.
But if water comes squirting out of this air valve, the captive-air bladder type water tank has burst or become torn or leaky, and repair is needed.
Thanks to reader Steven Prior for the photo (above left) showing water coming out of the air charge valve on a water tank. Most (not all) water pressure tank models using a bladder isolate water inside the bladder - meaning that water coming out of the air valve shows a burst bladder.
Note: Usually in a bladder-type water pressure tank the water is in the bladder and the air is in the tank outside the bladder. There are a few bladder-type water tank models in which this design is reversed - water is in the tank and air is in the bladder - more likely with fiberglass tanks.
A second symptom of burst water tank bladder: if air is found squirting out of plumbing fixtures it's possible that the cause is a burst bladder in the water tank; the tank's air charge is being forced out into the building plumbing system. This symptom won't normally continue once any excess air in the pressure tank has been lost - but the problem may remain, showing up as pump short cycling.
A third symptom of burst water tank bladder: if the water tank is full or nearly so and you are unable to drain water out of the tank, a burst bladder may be blocking the tank at its bottom. A burst water tank bladder can collapse at the water tank bottom, preventing water from leaving the tank. The result is no water pressure in the building and perhaps an inability to drain water from the water tank itself.
At WellMate Diagnosis we provide separate water tank diagnosis and repair advice for captive-air water tanks in which the air is in the bladder and the water is outside the bladder in the water tank.
Thanks to Jeff Garmel for suggesting text clarification in this discussion of water pressure tank diagnosis.
Water Tank Not Properly Located: if you place the water pressure tank too far from the pump pressure switch, or at a different elevation from the pressure switch, the pressure switch control may not operate properly. Here is what Amtrol™ says about tank location:
Really most pressure tanks will work if placed almost anywhere. But if you have a problem such as pressure switch bouncing (the switch turning the pump on and off rapidly at the start or end of a pumping cycle) you can relocate the pressure switch to the new larger tank and run a longer wire to the pump or pump control relay. Other causes of pressure switch bounce and well pump short cycling are explained at SHORT CYCLING CAUSES.
Repair of a leaky or burst water tank bladder: some people recommend treating the water tank as if it were an older bladderless type of water pressure tank such as the tanks we discuss at STEEL WATER TANKS.
It is unlikely that this will be a satisfactory repair. Usually when a captive air water tank bladder ruptures and water enters the rest of the steel tank, the bladder collapses; it often becomes impossible for the water pump to push much water into the water tank, and even if it does, the collapsing bladder will stick to and seal itself so that the water draw-down quantity before the pump needs to run again will be very small.
Our sketch at left, courtesy of Well-Rite water pressure tanks [Flexcon Industries]  Illustrates how air in the upper portion of the tank compresses water in the flexible tank bladder, acting as a spring to push water into the building water supply piping system during the draw-down cycle. You'll note that at the end of the 40/60 psi draw-down cycle illustrated, the voume of water in the tank is nearly zero.
Fixing or getting rid of a waterlogged collapsed-bladder water tank: as we mentioned above, it's also possible that the torn bladder will stick to the water outlet opening, blocking water from leaving the water tank. The result will be short cycling of the water pump. We discuss water pump short cycling at WATER TANK REPAIRS. In any case the drawdown volume will be reduced and it's likely that this misused water tank will rust through soon.
Reader Bill Kortebein described how he identified and repaired this problem.
You need to replace the water tank bladder or as most plumbers recommend, replace the entire water tank assembly. If you are going to drill a hole to drain a blocked water pressure tank, we suggest disconnecting the tank entirely from its fittings and using a hand truck to get the heavy tank outdoors before drilling into it.
Water tank bladder replacement: on some water pressure tanks, the water tank can be disassembled and the bladder replaced. You might want to ask your plumber to try this repair before replacing the entire water tank assembly. Bladder replacement will involve draining water from the system and removing the water tank pretty much as if the whole tank were to be replaced. Suppliers such as Wessels offer replacement bladders for some models of expansion tanks and hydropneumatic tanks. In general, if you're going to hire a plumber to do this job, we recommend replacing the whole tank.
Water tank bladder air pressure adjustment: Be sure to review WATER TANK BLADDER PRESSURE ADJUSTMENT if you are adjusting, tuning, or replacing the air pressure in your bladder-type well tank.
Frequently Asked Questions (FAQs about Water Tank Bladder Diagnosis & Repair
Question: Water tank internal bladder is stuck - how do I repair it?
I just replaced a bad water tank with a new pre-pressure tank. The pressure setting is at 29 psi according to the manufacturer. However, after hooking everything back up, it appears no water is going into the tank. I attempted to adjust the pressure switch but nothing appears to work. Could I be dealing with a back pressure switch? - Ron
Thanks for the information on the new pressure tank.
If the internal bladder has failed and collapse onto itself, can I get everything working by removing all the air pressure first and then pumping water into the tank?
There is water coming out of the water valve prior to the tank when the pump is running. However, after closing it, it appears no water is going into the tank. - Ron
Similar question: new bladder tank installed, tank won't fill with water
I just installed anew bladder tank, and it is not filling with water, is this normal? - Wess Wellmaker
Reply: Replace the Bad Air Bladder or try Pumping Up a Stuck Water Tank Internal Bladder
I'd check the pressure at your new pressure tank at the pump cut-in and cut-out points. If the pressure never changes then I'd agree that something's wrong with the hookup and no water is being pushed into the tank. If an internal bladder has failed it can collapse onto itself, stick to itself, and can prevent water from getting into the tank. But first make sure there is no closed valve that ought to be open;
A bad pressure switch would prevent water from entering the water tank if the switch is simply not turning on the pump when it should. ;
Next: when an internal bladder has collapsed and stuck to itself I think the "fix" is to replace the bladder or the entire tank and bladder assembly. No water enters the pressure tank when the bladder is stuck like that.
Since your tank is new, replacing the tank or bladder does not sound like the place to start. But even a new water pressure tank that uses an internal bladder could be having a problem filling the bladder the first time.
But according to Jeremy Rasmussen, an experienced well driller and installer, he sometimes can "un-stick" a jammed or stuck water tank internal bladder by temporarily forcing the well pump to pressurize the water tank to a pressure above the usual pump pressure control switch cut-off setting. Jeremy holds the pump relay switch closed to force the pump to keep running to increase the pressure against the stuck bladder.
Watch out: Especially if there is no pressure relief valve on the water tank there is a risk of bursting the water tank. Over pressurizing a water tank can cause it to explode, causing injury or even, as happened in New Paltz, NY, death. Watch the pressure gauge, and keep the tank pressure well below the recommended manufacturer's maximum pressure rating for the tank. If you keep the pressure below 70 psi and the tank is not already weakened by rust or damage, you should be OK.
Watch out: there are potentially fatal electric shock hazards if you touch live electrical wiring, especially in wet areas or where you may also be touching building plumbing.
Finally, check to be sure that any valves between the water pump and the pressure tank are "open" to allow water into the tank.
Wes: indeed water should enter your water tank bladder when the pump cycles on. Look for
- a closed or broken water control valve between pump outlet and water tank inlet
- a stuck water tank bladder (try briefly holding the pressure switch closed to pump up to 1o-15 psi over the usual cutoff pressure to see if you can un-stick the bladder in the tank
Watch out: do not overpressurize a water pressure tank - it can burst and kill someone
Question: bladder tank pump system worked fine until we had a burst water pipe
Hi there, we have a bladder tank pump that was working perfectly ok until Friday night when a pipe in the kitchen burst, and all the water was turned off. Now the pipe is fixed and the water back on, but the pump will only run for a few seconds and then goes off. It also isn't pumping much, if any water into the cold water tank in the loft (just a trickle running into it, mostly after the pump has switched itself off), and the other problem is, there is no water from any of the hot taps in the house.
The hot water tank is full. All valves had been turned back on. Even running the cold taps won't make the pump come on and stay on. It's currently sitting at approx 2bar, and when it runs, it cuts out at 3bar. These figures are usual for our pump. Any clues on why its cutting out too early and why theres no water coming from the hot tank to the tanks? Any advice gratefully received! - Jack
*Sorry, that last line should say "Any clues on why its cutting out too early and why theres no water coming from the hot tank to the taps?"
Jack I wonder if the burst pipe water flow rate stirred debris in the system and clogged the pressure sensor switch. Sorry not to have replied sooner, we were deluged with questions
Question: Water pressure tank seems to be empty and water pump won't shut off
I gently rocked the tank and it does not seem there is any water in it. My pump will pump water but the water pressure will only go a little over 30 so the pump will not shut off. For now I shut it off manually and turn it on and allow it to run until we have finished taking a shower or some other task. If the bladder has failed shouldn't the water pressure still build up and then shut the pump off? - Dale
If the internal bladder in a water pressure tank has failed, the symptoms can vary a bit. Sometimes a collapsed bladder will prevent water from entering the tank, or water can enter up to the pump cut-off pressure but water won't flow back out of the tank. If that's happening the pump will turn on and off quickly as if there were a waterlogged water tank.
Question: Buried water pressure tank, now the tank seems waterloged
Hi. Very informative site. I have a well system that was put in 6 years ago. The bladder or diaphragm tank was buried according to my installer because my double wide had no basement. He also told me the tank would be good for about 20 years.
Recently, I've experienced the symptoms of a waterlogged tank, and after discussing it with the installers front office find they warranty for 5 years (a long way from 20, but I'm certainly not calling them for any further work). 2questions: I'd like to install a new tank in an insulated box under the double wide--is this ok? I'm also wondering if I can just use the existing line coming out of the ground and temporarily not worry about digging up the old tank and rerouting the line. Thanks for any help. - Anonymous
Anon: in my OPINION, no one in their right mind would bury a conventional water pressure tank. The tank is not intended for being buried nor for soil contact, nor are its safety controls such as the pressure relief valve that should have been installed at the tank, nor are the pressure sensing controls that should be installed at or close to the tank. Such an installation cannot be serviced.
When you dig up and replace your buried water tank, if it cannot be installed inside the building in a dry heated space, it can be installed in a dry, covered, but accessible "well pit" as was common practice at well heads before the pitless adapter was invented.
Question: water pressure starts strong but quickly falls off to nothing - what might be wrong?
When we first turn on outside faucet near well house we have alot of water pressure, then it goes down to a trinkle in a few minutes. Also when we have this outside faucet on, we don't have any water in the house. Our pressure tank feels empty, could the bladder be collapsed? If it is collapsed, is there a way to get it uncollapsed or do we need to replace it? - Jorg
We were also wondering if the pressure switch could be causing the drop in pressure?
Jorg about the water pump pressure control switch, a bad switch will fail to turn the pump on or off at the proper time; if it were improperly adjusted it might appear to work but lead to lower water pressure.
Question: Water tank pressure creeps up higher than normal
My pump cut in pressure is 35 psi. Couple yrs ago charged tank to 33 psi. Recently my punp started short cycling. I drained the tank. Air charge read 46 psi. Lowered back to 33 psi. A few days later tank pressure was back to 46 psi. What could cause this? I changed the filter. Water flow seams normal. - Kevin
Kevin: these are great water pump and tank mysteries, no?
If you are seeing air discharge at your plumbing fixtures, see AIR DISCHARGE at FAUCETS, FIXTURES
Question: Why is there red cap over our water tank air valve?
Why is there red cap flush mounted inside of the air valve? It blocks access to the stem valve. - Lawrence
Reply: The red cap prevents accidental release of or change in the water tank's air charge
The red plastic cap on the air valve on your pressure tank is intended to prevent an amateur from messing with the tank's pre-charge of air pressure.
On many internal bladder type water pressure tanks, the water tank is provided from the factory with the manufacturer's recommended air pressure pre-charged in the tank. The manufacturer doesn't want someone accidentally letting the air out or otherwise messing with the air pressure charge if they don't know how it should be set.
Provided you follow the manufacturer's instructions about adjusting the pressure in the water tank, you can remove the red guard to access the air valve itself.
Question: how to troubleshoot air in water lines - collapsed water tank bladder as a cause?
Hi, What a helpful site. We have been experiencing intermittent air in our water lines, and yesterday had the well company come out. They repaired a couple things: pinhole found in pipe just above the submersible pump (which is 24 years old but appears to be running well). Also a weird bleeder valve arrangement that is no longer needed, and which he replaced with a brass check valve.
Put everything back down in the well and ran the water, seemed okay. However since then we notice very low water pressure, and when the water is on the pump is short-cycling. From reading your articles, I checked the water tank (well-x-trol) and am able to rock it with gentle pressure, leading me to believe there is no water in it. The pressure gauge is at 60%. My question is, is a collapsed bladder a common result of draining all the water from the system? And I guess the real question, is this repairable or do we need a whole new water tank? Thank you. - Sara
I haven't run across collapsed water pressure tank bladders due just to emptying the system of water, though I could imagine that if a tank were left empty for some time, the bladder might stick to itself. Bladders in at least some water pressure tanks are replaceable - some readers have reported success in doing so. Replacement involves shutting down and draining the system, and most likely disconnecting the tank to upend it to gain access to a removable panel through which an OEM replacement tank bladder is installed.
See AIR DISCHARGE at FAUCETS, FIXTURES for help in diagnosing and fixing the air discharge in your water piping and fixtures.
Question: water tank removal: how do I abandon a well and water pressure tank when switching to municipal water supply
I have had a water well plumbed and changed to a public water. the blue tank i was told was not in use,,though there was a leak from it. eventually it got rusted and at the end and let away the water from my public connection out. i had to turn mains off..what is going on if this belly tank only belongs to the water well, which is not in use. - Reosemary
Rosemary, if you have switched from well water to municipal supply, ALL of your old water input/supply equipment should have been taken out of your water supply system. That's because the municipality worries that contamination in a private residence's equipment could back-contaminate the public water mains.
Question: We have intermittent water pressure and the water smells - is it a bladder problem?
We are currently experience intermittent water pressure and water has slight smell. In conversing with other people thought our holding tank might have had issues w/the bladder. We haven't lost water completely and as of last night was on full pressure. Any ideas on the problem? - Karin Wilson
Reply: Diagnose the cause of intermittent water pressure first, and smell second
I'm not sure what to diagnose from your description; there could be a less-than-obvious connection between a water smell and water pressure in that in some wells, when the water level in the well drops (as it may seasonally especially in the dry season) there may also be an increase in odor in the well water as different rock fissures and different components of the aquifer feed into a typical drilled well at different depths.
Certainly we've seen that sulphur odors in well water can vary seasonally.
You could also have a problem with bacteria in the water supply or growing in the water pressure tank.
To be more diagnostic we need to understand if your "intermittent water pressure" means that at different times of the day water pressure is poor versus poor or inadequate water pressure during different portions of the pump cycle (typically just a few minutes). If it's the latter, then we might try addressing the complaint with an adjustment to the pressure switch to slightly narrow the gap between cut-in and cut-out pressures.
But if the water pressure failures are intermittent during the day, it sounds like there may be a well flow problem.
Question: why is my well and pressure tank water draw-down cycle only giving me 2 gallons of water before the pump has to turn on - short draw-down cycle troubleshooting
I have a private well with a new 7-8 GPM pump set at 300ft installed last year. I have been trying to test our 15 year old pressure tank. It is a WellxTrol WX-202 20 gallon that states it should have a draw down of 6.8 gallons. I have no pressure or flow problems and my pressure switch is set to 30/50. I ran a draw down test with my garden hose and nozzel hooked up to an outside faucet and only got 2 gallons before pump turn on (at 30psi) into a volume marked pail, but the draw down time was about 1 minute 30 seconds. Time from cut-on to cut-off (50psi) is about 15-20 seconds. There is no short cycling, at least from cut-off to cut-on and we get consistent pressure and flow.
OK, new information after an additional test this morning. I flushed a low volume toilet and the water tank pressure immediately went from cut-off (50psi) to just above the cut-in pressure of 30psi, then as the volume of toilet flow slowed the pressure slowly went down to cut-in pressure. I'll test the tank air pressure later but it looks like I need a new pressure tank. - Peter
Reply: check for a waterlogged water pressure tank, check the air volume controls, add air to the pressure tank
Peter, your description sounds as if the water tank is waterlogged - has lost its air charge. See SHORT CYCLING DIAGNOSIS TABLE for help in confirming and diagnosing both short water draw down cycle (too little water before the pump turns on) and frequent pump on-and-off cycling.
And see WATER TANK AIR, HOW TO ADD for help in getting air back into the pressure tank.
Reader follow-up: trying to get air into the water pressure tank
I drained the pressure tank from the well head so that the pressure gauge showed zero. Then tested pre-charge and found it to be less than 10psi. I added enough air to get 28psi (cut-in 30psi) then tested the performance. From zero to cut-off took much more time than before, at least double (guess-ta-met), and when I flushed the same toilet the pressure went to 42psi, not the 32psi I got before. So defiantly the problem was too little air pressure.
I don't know where the air went though? One thing I noticed was that as I was filling the tank with air the water pressure gauge also went up and I found I had to open the well head tap to get back to zero. This seemed to clear out and I can only assume that the bladder did not fully collapse until air pressure was added.
I re-checked the tank pressure after I had opened the well head tap and the pressure held at 28psi, so I think my bladder may be OK and not (at least completely) ruptured. I'll check the pre-charge in a couple of weeks but I think for a 15 year old tank I'll just replace it anyway. The original plumber only used the smallest marginal tank so I'll go bigger for more draw down. - Peter
Peter if you drain water out of a pressure tank down to low or "zero" pressure, that does not alone assure that you've actually gotten air to enter the tank. It could be still nearly full of water but at little or no pressure. You should be able to see at least 30 seconds of draw-down at a typical faucet before the well pump has to turn on. Or taken another way, a water pressure tank is rated for an "equivalent" draw down volume of water, typically 10 gallons or higher, if the tank is properly installed and air-charged.
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