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How do I replace a water pressure tank?

The bladder seems to be leaking. Water pressure in the house was getting weaker, and the tank was switching on too frequently, so I switched off the power and drained the tank. After powering back up it seemed to fill about 1/2 full and pressure in the house was restored to about normal...for about a month. I believe I just need to put in a new pressure tank but HOW?

The house and tank are 8 years old, and here are the specs of the current one:

Do it Best
Well System Tank (about 36" tall, 15" wide)
Factory Precharged Pressure 28psig
ID #16231429
Max Working Pressure 100psig

What kind should I get and what directions do I follow to replace it?


Re: How do I replace a water pressure tank?

I copied the info below from a Goldhiller post quite a while back so that I would have it for future reference when my tank needed to be re-charged. It discusses how to re-pressurize a tank. You may want to go through those steps before deciding you need to change out the tank.

From the Goldhiller post.....
All of this leads us back to your question and the figures you offered. Presuming a WX-202 tank with 5.9 gallon drawdown on 40-60 switch with 38 psi pre-charge and a 5 gpm pump.......it should take a bit over a minute to refill your tank. The actual refill time is determined by opening a nearby faucet ( or use the drain valve on the tank setup) just until you hear the pressure switch kick-in, then immediately closing that faucet and timing the refill (switch kicks out and pump stops). If a WX-202 tank, a 40-60 switch, a 5 gpm pump and the refill time is less than a minute.......then it likely indicates that your pre-charge needs to be adjusted. Too much water currently and consequently not the ideal amount of air. Wouldn't surprise me as some air sneaks thru even the best of bladders/ diaphragms over time.
The easiest and bestest way to check and adjust the pre-charge is to turn off the well pump, then drain the tank of all water via a hose connected to the hopefully present drain valve on the tank setup, then check the precharge via the Schrader valve (tire valve) on the tank with a tire gauge. If a 40-60 switch, the recommended pre-charge should be 2 psi less or 38 psi. It can be adjusted even closer than that, but a 2 psi difference is the usual recommended difference to insure that the switch kicks in the pump when it should.
If you're lucky, the installer placed a valve on the main delivery/output pipe between the tank and the house distribution pipes. If so, close this valve first to isolate the house-side plumbing from the procedure so as to avoid getting air in the house lines while you drain the tank and check things out/adjust air pre-charge in the tank. If you drain the tank with the hopefully present tank drain valve, then you can also check to see if the internal water/air separating bladder/diaphragm is torn at the same time. *If* when you totally drain the tank.....you hear a whoosh of air escaping at the end of the draining.... that would indicate a torn bladder/diaphragm. If you don't, then it likely means your bladder/diaphragm is still intact.
If in tact or not, close the drain valve and check the pre-charge with a tire gauge and use an air compressor to bring the pre-charge up to where it should be (about 2 psi less than the kick-in on the switch). Or.....you can add a bit too much air pressure, then turn the pump back on and let some air out of the tire valve until the switch kicks in and the pump starts. This would give you the very tightest workable adjustment of the pre-charge.
(If someone adjusted a factory set 40-60 switch to run a cycle of 45-65 instead, then your precharge should be 43psi or so)
If your pump is actually an 8 gpm pump, the tank is a WX 202 with 5.9 gal drawdown on 40-60 switch........then that 30-40 seconds refill time you indicate in your post would be about right if the tank has the right pre-charge. It's all just a very simple math equation.
If there is indication that the bladder is torn, then you'll probaly want to replace the tank with a new one. If the installer did a nice job, there should be a pipe union near the bottom of the tank that will provide for swapping out the tank with a new one in about 15-20 minutes.....if currently set up on a galvy or brass threaded pipe tank-tee and not sweated copper pipes. If there is no union presently, then the swap out time will likely increase as more plumbing will have to be taken apart and put back together.

Re: How do I replace a water pressure tank?

In hopes of simplifying this a bit...

Can you post a couple pics of your current tank setup? One (or more) overall showing the general plumbing situation and one (or more) taken down very low-ish/near the bottom of the tank.

If this is a bladder tank then it will most likely have just one pipe emerging from under the tank. How and with what it is currently plumbed will tell us much about how easy.. or not...it might be for you to attempt replacement yourself (type of pipe, existing fittings/connections, etc.) A picture of all that might be worth a thousand words....or more.

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