Pump does not run or just hums:

1. Line circuit breaker may be off, blown or loose.
2. Cord prong may not be making contact in receptacle.
3. If all symptoms check okay, motor winding may be open; take to authorized service center for check.

Pump runs but does not deliver water:

1. Check valve may be installed backward. Arrow on valve points in direction of flow.
2. Discharge gate valve, if used, may be closed.
3. Pump may be air locked. Start and stop several times by plugging and unplugging cord. Check vent hole in pump case for plugging.
4. Ion Technologies pumps have a small air vent hole in the impeller cavity to let out trapped air. If this hole becomes plugged, pump may air lock. To break the air lock, use a small screwdriver to clear hole in the impeller cavity.
5. As a secondary precaution in installations of this type – 1/16″ hole should be drilled in the discharge pipe below the check valve. The check valve should be installed in pump discharge above the cover on the basin.
   
   Note: In sumps where the pump is operating daily, air locking rarely occurs.
   
   
6. Pump head may be too high. Pump cannot deliver water over 24' vertical lift. Horizontal distance does not affect pumping, except for friction loss through the pipe.
7. Inlet in pump base may be clogged. Remove pump and clean out openings.
8. Impeller or volute openings may be plugged or partially plugged. Remove pump and clean out

Pump runs but delivers only small amount of water:

1. Pump may be air locked. Start and stop several times by plugging and unplugging cord. Check vent hole in pump case for plugging.
2. Pump head may be too high. Pump cannot deliver water over 24' vertical lift. Horizontal distance does not affect pumping, except loss due to friction through discharge pipe.
3. Inlet in pump base may be clogged. Remove pump and clean out openings.
4. Impeller or volute openings may be plugged or partially plugged. Remove pump and clean out.
5. Pump impeller may be partially clogged causing motor to run slow, resulting in motor overload. Clear impeller.

Fuse blows or circuit breaker trips when pump starts:

1. Inlet in pump base may be clogged. Remove pump and clean out openings.
2. Impeller or volute openings may be plugged or partially plugged. Remove pump and clean out.
3. Pump impeller may be partially clogged causing motor to run slow, resulting in motor overload. Clear impeller.
4. Fuse size or circuit breaker is too small. 5. Defective motor stator; return to authorized service center for verification.

Motor runs for short time then stops. Then after short period starts again. Indicates tripping overload caused by symptom shown:

1. Inlet in pump base may be clogged. Remove pump and clean out openings.
2. Impeller or volute openings may be plugged or partially plugged. Remove pump and clean out.
3. Pump impeller may be partially clogged causing motor to run slow, resulting in motor overload. Clear impeller.
4. Defective motor stator; return to authorized service center.