Replaced a 10yr 1.5 HP Jaccuzi Magnum force pump (pump had a flapper acting as check valve inside basket) with a 2 speed 1.5 HP Pentair Whisperflo.
All works except pump slowly loses prime when shut off. Pump basket half full after 3 hours of pump being off.
-Detected one leak before pump when pump shutoff and water squirted out. Added additional PVC glue. No more water detected when pump shuts off.
-Added PVC tape and solvent to all PVC male thread and PVC unions.
-Used red food color at all connections before pump and no detection.
-With pump off and inbound valves shut I get slow bubbles coming pump intake up to the glass cover. I would have thought I would see leaks since all connections are below pump basket.
-The chlorination system and other system between heater and filter not used for several years.
-Spa drain (closed valve) typically closed during normal pump operation.
-I might have had this problem all along and the previous pump with flapper minimizes the issue.
Any idea on what to check next.