Pressure Tank Switch shuts off intermittenly
We live on a hill. The well and storage tank are down below. The storage tank pump pumps the water up to the pressure tank on the side of the house. During all of this problem time, the storage tank has remained full, with the storage tank pump running, but the pressure tank not filling. I have a Square D pumptrol, on 30/off 50 pressure switch. I had a plumber come out after not having water in the house for 3 days and he partially flipped the pressure switch, held it for about 10 seconds and the tank began to fill. The pressure switch gage bounced between 30 and 50 until the tank filled. Nothing chattered. He said the pressure switch seemed to be working and maybe there was some ice in it (?). Now every other day of so, I have to go out to the pressure tank house and do the same thing to get water into the house. As soon as I do this I noticed that the gage immediately jumps to 40 and does't take long to (seconds) to have water in the house, then the switch shuts off, leading me to believe the pressure tank is already full. Can you adivse, please?