my pump is s deep well pump, the problem,this happens only some time, when the washing machine is turned on and we use water some where else that the pressure falls and the pressure switch on the tank is closed and i can fill the pump running by placing my hand on the pipe but the prussure will not come up stayes at 20 lbs, if i turn the breaker off and then on again the tank will fill up and the pressure returnes to 60 lbs. no one seems to know how to help: