Eric H
Well-known member
I thought that after 22 years I’d seen it all or at least had enough experience to diagnose any problems.
I have a Cat 530 that seems to lose prime. When the customer selects a high pressure function the pump runs there doesn’t seem to be any water in the pump.
This is an old Monorail system that is typically trouble free. The hot water tank gravity feeds the pump through a 2” pvc manifold then to a swing check valve. The cold water is also gravity fed from a tank that is higher than the hot water tank. When the cold water solenoid opens the pressure from the cold water tank pushes the swing check valve closed.
I thought that maybe the swing check was sticking either open or closed so I replaced it with a plunger type check valve...problem still exists.
Any advise before I keep throwing parts at this? I am going to open the 2” pvc manifold just to make sure there isn’t anything causing a blockage but I doubt this is the case.
I have a Cat 530 that seems to lose prime. When the customer selects a high pressure function the pump runs there doesn’t seem to be any water in the pump.
This is an old Monorail system that is typically trouble free. The hot water tank gravity feeds the pump through a 2” pvc manifold then to a swing check valve. The cold water is also gravity fed from a tank that is higher than the hot water tank. When the cold water solenoid opens the pressure from the cold water tank pushes the swing check valve closed.
I thought that maybe the swing check was sticking either open or closed so I replaced it with a plunger type check valve...problem still exists.
Any advise before I keep throwing parts at this? I am going to open the 2” pvc manifold just to make sure there isn’t anything causing a blockage but I doubt this is the case.
