Well Bladder Tank Pressure

[Ffltstn]

Hello,
I have a 4 year old AO Smith 86gal bladder tank that when I checked the air pressure it was Zero.
(I was replacing the pressure switch because it didn't seem to be turning on correctly)
There is not any water coming out of the valve, and the tank drains empty.
I can hook up a compressor and start to get build pressure until I open a faucet and the reading goes back to zero.
Can I have a bad bladder without it taking on water, or is there someting else going on?
Thanks,
Ken In FL

 

[Bannerman]

hook up a compressor and start to get build pressure until I open a faucet and the reading goes back to zero.

Pre-charge air added to the tank, is to be performed while the tank is completely drained of water, and while the drain valve remains open.

If the tank continues to not hold air, that is an indicator that the flexible internal diaphragm/bladder is damaged, or the tank shell has rusted through and so the tank requires replacement.

Suggest upgrading your well water delivery system with a Cycle Stop Valve, PK1A kit, which includes a new pressure tank, pressure switch, wall mount brackets and fittings along with the CSV. With the CSV controlling the flow rate from the pump to match the rate of water consumption at constant pressure, the pump will no longer cycle when more than 1 GPM is flowing to fixtures. This will then eliminate the need for a large pressure tank such as your current 86 gallon tank which will have an approx 23 gallon drawdown capacity, instead, usually utilizing only a 4.5 gallon tank with about 1 gallon drawdown capacity.

CSV PK1A PSide Kick kit

 

[Sponsor]

 

[Reach4]

I can hook up a compressor and start to get build pressure until I open a faucet and the reading goes back to zero.

I presume you mean air pressure.

While there are a few with bladders, most pressure tanks use a diaphragm. If water leaks up above the diaphragm, you can still get air coming out of the Schrader valve, because that valve is on top.

Your pressure switch might not have been at fault at all, if the problem was that you got short cycling. When you reduce the water pressure to zero, the tank will be light. If there is water trapped above the diaphragm, not so light.

 

[Ffltstn]

When it is empty there doesn't seem to have any water in it at all. If I leave the drain open and apply air it pushes the last of the water out of the other tank. I put everything back togetether and it feels and sounds like its full of water. I think I need a new tank.
AO Smith has a 5 year warranty but says not for outside. I'm in FL no chance of freezing but they may deny my claim.
Thanks Everyone.

 

[Bannerman]

If I leave the drain open and apply air it pushes the last of the water out of the other tank.

A diaphragm pressure tank is one tank which is divided into two chambers - an air chamber and a water chamber which are separated by the flexible diaphragm.

If water exits from the drain valve (water chamber) when air is added to the tank's air chamber, perhaps some water was remaining in the water chamber, so the additional air pushing against the diaphragm is then pushing the water out from the water chamber.

More likely, water has leaked through a ruptured diaphragm into the air chamber, so adding air is causing some of the water to be pushed back into the water chamber, which is then draining out through the open drain valve. Depending on the location of the rupture, there maybe a large quantity of water continuing to remain within the air chamber, even after water stops draining from the drain valve. This is usually made evident by rocking the pressure tank from side to side after water stops draining.

The lifespan of the pump, pressure tank, pressure switch, check valve etc, is reduced by excessive pump cycling. The addition of a CSV, will eliminate pump cycling, which will extend the lifespan of each of those various components, and will also eliminate the need for buying another large and expensive pressure tank.

 

[Valveman]

When it is empty there doesn't seem to have any water in it at all. If I leave the drain open and apply air it pushes the last of the water out of the other tank. I put everything back togetether and it feels and sounds like its full of water. I think I need a new tank.
AO Smith has a 5 year warranty but says not for outside. I'm in FL no chance of freezing but they may deny my claim.
Thanks Everyone.

It is not being outside and rusting that causes the diaphragm to fail, it is cycling on and off too much. The PK1A kit with the 4.5 gallon tank will do a better job than an 86 gallon size tank. The CSV will also deliver strong constant pressure instead of the varying pressure that happens when the pump is cycling on and off repeatedly.