I have a brand new wellsaver pressure tank. I have set the pressure switch for 30/50. This part of it seems to be working well, but every time I have checked the pressure in the tank I get different readings. Anywhere from 24psi to 40psi and then back to 24 then to 32 and so on. I want to get it to 28, but I am not sure why I get the strange readings. The pump seems to be running well, but it doesn't kick on sometimes until 24 or 26psi. Any info would be appreciated.