I just recently purchased a house with an inground 20x40 IG pool. Three days after moving in the motor on the pump blew. I sat on this for a while and replaced the pump and motor this past week. When the pump is off the pressure reads at 16psi, when I turn it on it shoots up to 32 psi, 30 psi when the polaris is on. I backwashed the filter already but that didn't do anything to relieve the pressure. What should I do because I am almost certain that a fluctuation of 16 psi is too much?