1-Check electrical connections, fuses or size and length of power cable. Compare the pump motor rating, printed on a label on the side of the motor and on the serial number tag, to the power source, to be sure they agree in voltage, phase, and frequency.
2- The ambient temperature is too high
3- Cooling air supply is insufficient
4- Fan is not working or disconnected
5- The process gas is to hot or throughput is too high
6- OVERLOAD PROTECTION - Motor thermal overload protection is made available by the motor manufacturer as an aid to minimize motor failure. Overload protection is a standard feature on both 50 and 60 Hz single phase-motors. The motors have automatic overload protection. Automatic reset protection is designed to reset itself after a predetermined cooling period. If the fault to the drive remains unaltered, the motor will cycle on and off until the fault is corrected.
7- Debris lodged in pump preventing pump from turning (may trip overload protector).
8- Exhaust is blocked or clogged - The pump will not be able to turn if exhaust gasses cannot leave the pump freely. Restrictions in exhaust, partial or full will prevent the pump from turning intermittently or completely. Try running with exhaust filter or exhaust line disconnected. Pump may not start if exhausted into another vacuum system, such as a house vacuum system.
9- Bad motorContact Us for additional trouble shooting, do-it-yourself repair assistance or to have your pump repaired by us.