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This article describes how to add air to a building water pressure tank and it reviews the function and repair of water tank air volume controls or snifter valves in a building water supply system where a private well is the water source. Quite often a short-cycling well pump problem can be traced to loss of the air charge in the water pressure tank. This article describes three alternative methods for fixing that problem. Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman. How to Add Air to a Water Pressure TankThere are fancier methods than those described below but here are three simple methods for fixing a waterlogged water pressure tank, of which the second two work well for easy replacement of air lost from a water storage or pressure tank.
Other water tank problems such as air leaks, water leaks, or a damaged or burst air bladder, or pressure control switch problems can also make a water system behave improperly. See the links listed at Related Topics or start at WATER TANK REPAIRS for these. Below we provide a short summary of these methods for adding air to a water tank, and we provide links to in-depth detailed procedures. 1: AIR VOLUME CONTROLS - Method 1: air-volume controls on water tanks
2: Use the water tank air inlet valve or tire valve or "schrader valve" to pump air into the tank
3: Drain the water tank using a garden hose and allow air to enter the tank
Other water tank problems such as air leaks, water leaks, or a damaged or burst air bladder, or pressure control switch problems can also make a water system behave improperly. See the links listed at Related Topics or start at WATER TANK REPAIRS for these. More about how we get air into the water pressure tank to avoid well pump short cycling
... Frequently Asked Questions (FAQs) about how to add air back to a water pressure tankQuestion: Do you need to shut off all faucets when putting air into the water pressure tank?After draining the system and turning off the well pump, when you re-inflate the water tank to pressure, do you shut off all the faucets again to recharge the tank? Or should the water tank hold air pressure even with the faucets open? - Takafoomi Thank you Dan for the quick response. I do have a blue pressure tank with a bladder. Upon draining the system, there was not enough air pressure to register on the tire gauge. My Square D, a 30/50, seems to be cycling a fair amount more than it should be as of late. I suspect that the bladder isn't holding a charge of air very well based on what I've read. I just want to see if I can get it to hold some air to be certain before I explore replacing the tank.. which is about 10 yrs old. Reply: Don't fix an internal-bladder water tank just by draining it. You might need to shut off water into the home when adding air to a water tank.With an internal bladder tank typically the starting pressure with no water in the tank is 2 psi below the pump pressure control switch cut-in pressure. Draining tanks or adding air to water tanks with internal bladderIf your water pressure tank uses an internal bladder you would not be fixing a waterlogged tank by draining it - so the discussion below only pertains to a bladderless water tank. Water tanks that use an internal bladder are discussed at WATER TANK BLADDERS & CAPTIVE AIR. Draining tanks or adding air to water tanks that do not use an internal bladderIf you are using the complete tank drain down so that the tank is fully empty, then you won't be pumping ANY air into the water tank; rather, starting with a tank fully empty of water and at local normal air pressure will be enough. Details of that procedure are at WATER TANK AIR ADD BY DRAINING. If you are adding air to a water tank by pumping air into the system, details of that process are at WATER TANK AIR ADD AT AIR VALVE. In that case, if the air valve is mounted right on the water tank you don't need to close off water lines into the building, because air will be going right into the tank. If the air inlet valve is mounted on building piping such as at the tank tee at the bottom of the bladderless water tank, it will usually but not always work to just pump air in at that point - much of the air will flow into the water tank. But in this case it's best to turn off the main water valve where the line exits the pressure tank and would otherwise send water into the residence. Then place the air charge into the tank. For bladderless water tanks, don't worry if during the air pumping process some air enters the water piping in the direction of the well. That air will be pushed up into the water tank the next time the well pump cycles on. In fact that's just how snifter valves (discussed at AIR VOLUME CONTROLS, WATER TANK) work. Question: Why is the pressure in our water tank increasing and why won't the pressure switch kick on at low pressure?The air pressure in the pressure tank goes from 28 psi to 40 psi in just a couple of days and as a result the switch wont kick on at low pressure . any ideas on why it would take on pressure - Anon. Reply: Check for air leaking into the system, keeping the water tank pressure abnormally highFirst make sure that the pressure you are reading is air pressure, not simply system pressure. Inside a water pressure tank, both air and water in the system will (nearly) always be at the same pressure. If your water tank is one that does not use an internal bladder and if your well pump system is picking up air (for example from a leak in the well piping or a low-flow well) then the system could be sending a water-air mix at pump output pressure into the water pressure tank where air, naturally remaining above the water in the tank, is accumulating. If your water tank is an internal-bladder type that was installed to replace a bladderless water tank AND if your well pump is a submersible unit (located inside the well) it is possible that air is entering the water tank bladder (where it does not belong) because the water tank installer failed to remove the snifter valve and in-well air drain valve/air inlet valve that were previously used to maintain the air charge in the bladderless water tank. Details about snifter valves are at AIR VOLUME CONTROLS, WATER TANK. Question: Filling a swimming pool from the well resulted in low then lost water pressure - what might be wrong?yes, awesome site with tons of info. my issue, 2 days ago i helped my blind neighbor fill his approximately 5,000 gallon pool... the next day he had low water pressure. then the following day just dribbles. according to him, 2 months ago with another issue with a burst pipe, he had somehow, bleed the air from his tank. today i will be checking that pressure. it sounds like he may have burst the bladder or burned the submersible pump. PS: Little update... this morning we drained the tank. then checked psi, it is at 15 psi. tried to put in the 3 more lbs.. didn't take any, it seamed. did about 20 pumps from a bicycle pump.. no difference in pressure. Reply: problems that can occur when filling a swimming pool from a private well and pump systemBullweenkle Follow-Up from bullweenkle:man your good... there was no hum.... the pump was replaced yesterday at a cost of 1200$. it was put in 1961. was old anyway. BTW, 1st changed out the pressure switch. old also. ty John Question: Sporadic water pressure, fast, then slow, pump cuts on and off every few secondsI have a Well-X=Trol pressure tank. I have water in house, but it is sporadic, running fast, then slow, & pump cuts on & off every few seconds. There is water coming from the air valve when you push that. So I assume it is water-logged. Can I cut the power off, drain the tank, & turn it back on, let it fill, & it will add the air by itself? Please guide me so I can get this fixed. thanks - Gena Sager Reply: the most common cause of well pump cutting on and off rapidly is lost air charge in the water pressure tank.Gena, typically if you see water pressure varying significantly it's "fast" when the pump is on and "slow" when the pump is off and you're running off of the pressure tank delivery. Water out of the air valve suggests the tank is water logged, as you guessed too. Yes you can turn off power, drain the tank entirely, let it just fill with air by gravity, then close it up and turn the pump back on. (Watch out for losing pump prime). Details on how to do this are at WATER TANK AIR ADD BY DRAINING A clogged water filter can also cause the pump to cycle on and off rapidly. Question: when water is turned on, after a couple of seconds, it begins to surge and pulses harder and softer after that. Well pump pressure jumps to about 65 psi in about 5 seconds then the pump shuts offI love this website and appreciate the good work you are doing. I am trying to diagnose a problem with my well. I have looked through your site and I’m not sure I saw a problem quite like this one. The symptom is when water is turned on, after a couple of seconds, it begins to surge and pulses harder and softer after that. I live in Sacramento, have an outdoor well and tank which is 220 gallons, galvanized steel, and I believe to be bladderless. I have the pressure switch set to 40 -60 psi. When I watch the water pressure gauge, when the water is turned on, it goes down to 40 in about 7 seconds, the pump kicks in and it jumps up to about 65 psi in about 5 seconds and shuts off. It continues this cycle continuously while the faucet remains on. After reading your website, I was hoping I had a waterlogged tank. I shut off the power, opened the hose bib. The tank emptied pretty fast, but kept gurgling with little bits of water coming out every so often. I shut the bib off, restarted the pump and it did the same thing. It doesn’t seem to be filling the tank. Any ideas on how to proceed? Reply: Sounds like a waterlogged pressure tank.Max, Your description sounds like a water-logged pressure tank. Your observation that when you opened the hose bib "The tank emptied pretty fast, but kept gurgling with little bits of water coming out every so often." might mean that the tank was not really emptying at the hose bib. Rather the first water that came out was that which was under pressure. After that, the full tank was dribbling water slowly out of the hose bib as intermittently a little bubble of air found its way back into the tank to thus allow a little more water to escape. That gurgling dribbling at the hose bib may be another clue indicating a waterlogged pressure tank. How to recognize a waterlogged pressure tank and diagnose a short cycling well pump Under the article named WATER PUMP REPAIR GUIDE (links at Related Topics ) beginning with the article titled SHORT CYCLING WATER PUMP, you'll see some articles on the causes and cure of short cycling on-and-off of the water pump, which is usually the explanation for water pressure surging and pulsing as you describe. Three methods for fixing a waterlogged pressure tank: You're on this same investigation path, but it sounds as if you did not successfully add air to the tank. Just draining out some water, especially at first, is just draining out water that was under pressure. You need to get air into the tank using one of the methods we describe in this article (above). See these procedures for adding air at the water pressure tank: Also you might need to take a look at I've also seen this rapidly short-cycling water pump symptom when a water filter on the system is clogged or dirty. Because the well pump can't force water through the filter fast enough to keep up with flow in the building, it can cause the pump to cycle on and off quickly, causing water pressure to behave similarly. Reader Follow-Up: short cycling well pump fixed by adding air at the pressure tankI can't thank you enough for your website and quick response! I wanted to write you back and let you know the outcome of my little well issue. The surging water I described appears to have been caused by what you describe as “Well pump short cycling.” After reading (more carefully) your article: Well Pump Short Cycling: How to diagnose “Water Pump Short Cycling” and restore Air in a Building Water Tank [see this article at SHORT CYCLING WATER PUMP] and your response, I was hopeful that the cause was a waterlogged tank. I read your step by step instructions and it worked beautifully. Opening up nearby hose bibs and the schrader valve helped the water drain more quickly, but it still took several hours to drain the tank. Before I tried this, the tank was draining so slowly and gurgling, I didn’t think it was still full of water. It has been nearly a week the well is working perfectly now. Not only did you save me some money, but more importantly, fixing it myself was good for my self esteem. Thanks again! Comment-DF:Max, reading over your notes I add the observation that your 220 gallon water tank is larger than common in-building residential tanks (30-50 gallons) and may be an indicator that your well itself has a limited flow rate or water delivery capacity. When we have a well of limited flow, a solution (other than drilling a new well) is to install a very large water storage tank and allow the pump to fill the tank at a slow rate that doesn't exceed the flow rate of the well. That assures the building always has plenty of water. A worry, however, is that the slower the flow rate of a well, the higher the risk that it eventually stops completely. If you should need to investigate the well flow rate further, take a look at How Much Water is In the Well? or the well flow rate test procedures at How to Test Well Water Quantity and see How to Get More Water From a Well for help in increasing the well yield or flow rate. These and related articles are found at Related Topics under WELLS CISTERNS & SPRINGS Question: My well pump is cycling on and off and water is not entering the holding tank. How do I pressurize it?I need help. My well is cycling and the holding tank is not filling up with water. How do I pressurize it? There is a pressure valve on the pump. But I cant seem to locate a valve stem anywhere. HELP~!! - Tammy Reply:Tammy, there are three approaches to re-charging the air in a water pressure tank - please read about them in the article above. If your tank doesn't have an air valve you can recharge it by draining. Question: Submersible well pump growling noise during water tank recharge, vibration.I have a heavy growl when the well pump (submerged) recharges the well tank. I can feel the vibration in the hard plastic pipe from the pump; and, it telegraphs throughout the home's copper pipes. I used the gravity method to drain the tank. Pressure gage read 34psi when completely drained. When pump switch turned back on, pressure immediately jumped to 38; and, when tank allowed to run down, low-pressure switch kicked in at 38psi. This did not resolve the growl/vibration issue. But, when checked the Schroeder valve after performing above procedure, noted that tank pressure at valve is 44.5psi. Should I relieve the pressure at the Schroeder valve with the tank full, or empty? Should it be lowered to 36psi? If I still have the growl/vibration problem, could my submerged pump be wearing out? - Ron Reply: Check for a stuck bladder in a bladder-type water pressure tankRon, before changing the tank pre-charge pressure, see if your tank bladder is sticking to itself. A well driller recently suggested to us that he tries freeing up a stuck internal tank bladder by briefly and just one time, holding the pressure switch relay down to force the pump to a higher pressure TEMPORARILY. Watch out: - don't push the water tank pressure up past or even close to the rated tank pressure or you may burst the tank and worse, be injured. Question: I need to add air to my water pressure tank but I don't want to read all these instructions - what's a quick summary?Thanks so much for all the great work - but for purposes of actually adding air to my tank, I have to say it may be both too much and too little! Have cycled through several of the pages and page/links and still never found out step by step how to add air to my tank! Do I drain it first?... leave what valves open and what closed? Power on or off? Use my compressor after dropping pressure to the cut off point or just below or 0, or fill air pressure with the tank already full and pressurized..? what levels do I stop and start adding air with my compressor? Again... your tremendous efforts are really appreciated, but finding the answer I need is just too confusing, for me anyway. Reply: Quick overview of adding air to the water pressure tank
Question: When I shut off water at the pressure tank the tank pressure keeps dropping anyway. Do I need a new pressure tank?I am losing pressure at my well pressure gage with the water shut off leaving the water tank I put in 30 psi in the top of the tank and in 45 min its reading zero time for a new pressure tank ? thanks Karl Reply: Check for a leaky check valve or foot valve, at the pump, on the well piping, or at the well bottom; also check for well piping leak.Karl the water pressure tank could have a leak in itself, in which case you'd hear air hissing out or see water leaking out of the tank. But with the main water valve shut off (closed) between the pressure tank and the rest of the building, if pressure in the water tank continues to fall, the most common cause is a leaky check valve or foot valve. Depending on the pump type, there may be a check valve right in the end of the well pump (an above-ground one line jet pump) or the equivalent check valve may be at the end of the well piping (submersible pump and 2-line jet pumps). The check valve or foot valve keeps water and pressure from leaking backwards out of the pressure tank and back down into the well when the pump stops running. If this valve is leaky you'll lose water tank pressure (and water) back into the well and eventually an aboveground pump will lose prime and you'll lose all water pressure. A second cause of this same symptom can be a leak in the well piping itself, anywhere between the water pressure tank and the bottom of the well; Ask a Question or Search InspectApediaQuestions & answers on the procedures for adding air to a water pressure tank using one of three easy methods - how to stop well pump short cycling. Ask a Question or Enter Search Terms in the InspectApedia search box just below. Technical Reviewers & ReferencesRelated Topics, found near the top of this page suggest articles closely related to this one.
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