Water Pump Question

Pumping air or short cycling the pump motor? If the pump motor is rapidly cycling off and on, an adjustment of a screw in the pump head may help.

Only place for air to get in is on suction side of pump as the discharge side is pressurized and would leak water out.

Air would cause pump to loose prime...limit or stop pump from pumping water

Are you getting air out of faucets?

Water heater and or electric element wouldn't have anything to do with air getting in system....again it is also pressurized

Is pump 'chattering' or is check valve in WH Tank HOT out making noises?

For what it's worth, I was getting a lot of air with my water this summer. Turned out that a winterizing value was partially open -- the one that you open when you want to draw antifreeze through the pump. Closing that valve remedied the problem.