Main jet pump hums but does not start; may trip breaker after a few seconds.

Safety first: Turn off power at the breaker before touching the pump or wiring.

• 1. Check for obstructions: With power OFF, remove the pump union on the suction side and feel for debris in the impeller area. Remove any foreign objects.
• 2. Spin test: Try to rotate the pump shaft or impeller by hand (from the back of the motor if accessible). It should turn smoothly. If it is locked, the motor may be seized.
• 3. Inspect capacitor: Many Sundance jet pumps use an external start/run capacitor under a metal or plastic cover on the motor. Look for bulging or leaking. Replace with the same microfarad rating if defective.
• 4. Verify voltage (for technicians): Measure voltage at the pump terminals when it is commanded ON to ensure proper supply.
• When to call a technician: Pump motor replacement or capacitor testing should be done by a qualified technician if you are not experienced with electric motors.