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mellow mel
Jun 18, 2015, 02:40 AM
is it possible for a bladder in the tank to stretch over 15=years if it had too much pressure blown into it. Currently I had to release the pressure in the bladder, reducing inside water pressure at end of yuage cycle. Otherwise the bladder blocks the outlet, virtually cutting off flow, intil the pressure finally drops below PSI for switch to kick in. If I drain the tank and put in the factory PSI I will loose water for a minute or two. Thanks

hkstroud
Jun 18, 2015, 04:20 AM
Sorry but you have ruptured bladder.
The pre-charge air is between the tank and the bladder, not in the bladder. The water is pumped into the bladder. Excessive air pressure would not cause a bladder to rupture or leak because it restricts the expansion of the bladder.

Water will absorb air, especially water under pressure. The purpose of the bladder is to keep the air and water masses separate. What you have right now is the same as the old galvanized pressure tank. It will function for a while but will become water logged as the air is absorbed. As the air is absorbed it will take less and less water to move the pressure switch from the cut on to the cut off. You cannot compress water. Your pump will begin to short cycle. When all the air is absorbed the pump will come on each time you open a faucet and will shut off when you close the faucet.

You could then restore the tank by draining and adding more air, which is in effect what you just did..

jlisenbe
Jun 18, 2015, 06:09 AM
Be sure you have correctly charged the tank. The pressure should be set at 2# below the cut in pressure. So, if your pump cuts on at 30#, for example, then the tank pressure should be set at 28#. Do this with the pump turned off and pressure drained to zero by opening a lower level faucet. Measure pressure and add/remove air at the air valve at the top of the tank. I suspect your tank pressure is set too high.

If the bladder is ruptured, you will generally be able to find out by pressing the valve at the top for a few seconds. If water comes out, then you have a bad bladder. If it's air only, then you are likely OK.

hkstroud
Jun 18, 2015, 09:47 AM
If water comes out,

John,
That only happens if the tank is completely water logged

jlisenbe
Jun 18, 2015, 01:37 PM
John,
That only happens if the tank is completely water logged

Correct, which is why I told him it was "likely" he was OK if he did not get water. That might indeed be his problem, but to check the tank air charge is the much easier and cheaper first step.

I think you are suggesting that, if the bladder is ruptured, then it might be possible for part of it to lay across the outlet at the bottom and block flow. Could be.

hkstroud
Jun 18, 2015, 02:04 PM
You can check for a ruptured bladder if you let all the air out the shrader valve, then if you get water you have a ruptured bladder. No water after you let the air out, no rupture. Yes, if the bladder has ruptured and collapsed it can block water leaving the tank. Water can go in but might not be able to come out.

jlisenbe
Jun 18, 2015, 06:13 PM
Yep. That would work. What is unusual with this person is the fact that he did, on several occasions, bleed air from the tank charge to lower pressure enough to kick the pump on. He must have a pretty good air charge to be able to do that several times and yet not short cycle, or at least he did not mention that.