When faucet is turned on, I get a surge condition, water flows but the pressure gauge alternates back and forth rapidly. I turned off the power, opened the outlet valve and just a little bit of water drains out. I also checked the air valve stem at the top of the tank and found no air pressure. I removed the valve stem and no water came out.

No air was in the tank. I kept the outlet valve open, pumped air and checked the pressure until 40 pounds was reached. As air was put into the tank, more water flowed from the tank outlet valve. The surge condition stopped but now I do not know why the precharged air disappeared and where did it go? What is the diagnosis of losing the recharged air in the tank? Does it mean that the bladder has a small leak? Do I still require a new tank? Thanks

I would suggest to wait and see if bladder has a leak you will have water coming out from air valve stem, maybe you had air leak from the air valve stem, check the stem nozzle for leak, good luck.

John

Sorry but I think you have a leaking or ruptured bladder.
Two things you have to remember. One, water will absorb air, especially if the air is under pressure. Two, you cannot compress water.

If you have a ruptured bladder the water will over a period of time absorb all the air in the tank. That is where your air went.

You cannot compress water, that was why you go the surging.

You didn't get any water out the schrader valve because the pump was shut off and the water in the tank was not under any pressure.


I kept the outlet valve open, pumped air and checked the pressure until 40 pounds was reached
Not the proper way to set the pre-charge in a tank. You may or may not have the proper charge.

To properly recharge the tank, turn off the pump, Open the drain valve and a faucet (to let air in). When the tank is completely empty, set your pre-charge.

To check for leaking or ruptured bladder remove valve stem in schrader valve and let air out. With pump running see if you get water out the schrader valve. You need the pump running to provide pressure to push the water out if the bladder is ruptured.

Sorry but I think you have a leaking or ruptured bladder.
Two things you have to remember. One, water will absorb air, especially if the air is under pressure. Two, you cannot compress water.

If you have a ruptured bladder the water will over a period of time absorb all the air in the tank. That is where your air went.

You cannot compress water, that was why you go the surging.

You didn't get any water out the schrader valve because the pump was shut off and the water in the tank was not under any pressure.


Not the proper way to set the pre-charge in a tank. You may or may not have the proper charge.

To properly recharge the tank, turn off the pump, Open the drain valve and a faucet (to let air in). When the tank is completely empty, set your pre-charge.

To check for leaking or ruptured bladder remove valve stem in schrader valve and let air out. With pump running see if you get water out the schrader valve. You need the pump running to provide pressure to push the water out if the bladder is ruptured.

I left out some info, I did have an outside faucet open while I was emptying the tank. I will check the leaking or ruptured bladder as you stated tomorrow. Thanks.

I would suggest to wait and see if bladder has a leak you will have water coming out from air valve stem, maybe you had air leak from the air valve stem, check the stem nozzle for leak, good luck.

John
Will check for leaks or rupture tomorrow, thanks.

Note

Even if the bladder is ruptured, a tank with the proper pre-charge will work for a period time until the air is absorbed.