I know this is long, but I want to provide as much info as possible to get the best answers.
I have a Goulds V60 HydroPro well tank. The well pump switch had to be replaced several years ago, and in the process of doing that, noticed that the well tank had a small leak and was replaced with the V60. Lately I have noticed that the pump is coming on every time I flush the toilet, whereas in the past the pump wouldn't come on until the second time it was flushed (depending on how much water was used between flushes of course). The pressure switch on the pump was factory set at 30/50. The tank pressure was factory set at 38 psi. When the plumber put on the new switch and changed the tank, I don't know if he made any adjustments to either the switch or the tank, though I assume he would have.
I decided to check the pressure in the tank the other day. I shut the power to the pump, opened an outdoor spigot and ran out almost 10 gallons of water before the tank was drained. The pressure in the drained tank read 16 psi. I knew the tank needed 28 psi with a 30/50 pressure switch. However, when I attempted to add air to the tank with a small compressor the gauge on the compressor went crazy, reading well over 125 psi, though the max pressure for that tank is 125. I added air for about 30-45 seconds, checked with the tire gauge again and it still read 16 psi. I tried adding air a few more times, but got the same result.
I ended up cutting the power back on to the pump and the pump ran and tank filled. I put the tire gauge on the tank after the pump stopped and the gauge shot all the way out (it only reads up to 50 psi). There are no pressure gauges on the well so I can't look at that to tell what is going on.
Do I have a problem with the tank or the pressure switch? The tank isn't waterlogged, no water comes out of the schrader valve and after I drained it I gave it a little wiggle and it was very light, no water in it. Any ideas as to what the problem may be? I'd like to be getting a better drawdown so I don't decrease the life of the pump. The pump is running for about a minute and 15 seconds now, where it was running close to 2 minutes before.
Any help and advice is greatly appreciated!