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Identifying a replacement motor from its nameplate: HP, RPM, volts, amps, service factor, frame, enclosure, rotation and type

Buy the OEM part by the appliance's part number when you can. When you must match a motor by its nameplate, copy every field before you remove it and match the electrical side first (volts, phase, hertz), then the output (HP times service factor at least equal to the original), speed (RPM and number of speeds), rotation, and the mechanical fit (frame or mounting, shaft diameter and length, enclosure). Duty and insulation class must be equal or better. Type codes are maker-specific and only help with the same maker.

Cross-checked ~30 min moderateBrands: All

Before you start

  • Kill power and discharge any run capacitor before removing a motor
  • Dual-voltage motors: confirm the lead connection for the supply voltage before power-up (a 115 V connection on 230 V burns the motor out at once)
  • Compressors and anything in the sealed refrigerant system are not covered here (BLOCKED, EPA 608)

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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Identifying a replacement motor from its nameplate: HP, RPM, volts, amps, service factor, frame, enclosure, rotation and type · OnCall Tech