Bad pressure tank?

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Banjo Bud

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How do I know if my pressure is bad? Is there a test I can perform? I’m concerned the bladder is bad. The tank is 27 years old and is a 20 gallon. Thanks.
 

Reach4

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Note the turn-on (cut-in) pressure where your pump turns on.

Turn off the pump. Drain the water and sediment from the drain valve at the tank.

Note the air pressure. The air precharge is always measured and set when the water pressure is zero.

If your pump is submersible (down the well), set the air pressure to 2 psi below the cut-in pressure. If your pump is a jet pump (above ground), set the air to about 4 or 5 psi below cut-in. Jet pumps take a while to get really pumping.

There are more complex tests, but that should be a good way to proceed.

Also note that a tank empty of water is much lighter than one that has water. If you drain the tank, and it is still heavy, it is bad.

If you will keep the existing tank in service, flush it. Annually is usually a good idea.
Precharged Pressure tank flush:
1. Connect a hose to the sediment drain valve, and run that to where you plan to drain the water. I suggest filtering the output through a cloth if you suspect the sediment may include sand.
2. Turn off the pump.
3. Open the drain valve, and let it drain until the water stops. It would be possibly interesting to watch the first water that comes out.
4. Close the valve, and turn the pump back on, and let pressure build.
5. Repeat steps 2, 3 and 4 as needed.
 

Banjo Bud

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Got it thanks. My pressure switch is a 30/50. The tank seems good and I took a pressure reading when the pump cut off. The dial pressure gage next to the pressure switch read 55 and my tire gage on the tank read 53. Then I opened a faucet and let the water pressure drop until the pump cut on. Then I immediately turned the breaker off so the pump wouldn’t repressurize the tank. The system dial gage read 35 and my tire gage on the tank read 33. The whole reason I did this little exercise is to compare the system gage to my tire gage. So I verified that my tire gage was reading 2 psi less than the dial gage on my system. So then I opened a faucet and ran water until there was no more coming out. Then I put air in the tank until my tire gage read 31 psi. All seems good. Thank you for your help
 

Valveman

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It is very common for the tire gauge to read a few PSI different than the water pressure gauge. This is why I err on the low side with charging a tank. I prefer 35 PSI instead of 38, as too much air can cause problems.
 

Reach4

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Glad this is working for you. Another alternative for somebody else who has the low-pressure cutout occur sometimes would be to rotate the nut on the big spring about 1/2 turn clockwise. This would increase the cut in, and cut out, pressures by about 1.4 psi. (10 turns CW increases both by about 3.5 psi).

In theory, I would like to keep the precharge higher if there is not symptom by doing so. I figure the diaphragm will stretch less at cut-out. Plus, the air pressure usually drops slowly with time. People recommend checking the precharge pressure annually. I go much more-- maybe 5 years.
 

Banjo Bud

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This brings up a question. Can I change over to a 40-60 instead of a 30-50? Is mine a 30-50 because the pump isn’t capable of 60?
 

Banjo Bud

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I really have no idea. It’s at my dads house 10 hours from me. But I could ask him. Maybe he has a record.
 

Banjo Bud

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Here’s a picture of the underside of the well cap. I’m not sure what it all means.
 

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Reach4

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This brings up a question. Can I change over to a 40-60 instead of a 30-50? Is mine a 30-50 because the pump isn’t capable of 60?
As the pressure rises, is the pressure rise much slower as you approach 50 psi? If so, you probably don't want to raise it. Consider giving 35/55 a try first. Turning the nut on the big spring in the pressure switch 1-3/4 turns clockwise should increase 30/50 to about 35/55.

Don't forget to raise your air precharge to 33. Air precharge is set or measured while the water pressure is zero.
 

Valveman

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A submersible usually has not problem making more pressure. Just turn up the pressure switch and try it. If it doesn't get to 60 fairly quickly, turn it back down.
 
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