National Electrical Installation Standards

Standards as High as Your Own

Thursday, January 10, 2019


Clarification on a/c breaker On an air conditioner data plate. It states 35 amp Max OCPD Minimum Circuit Ampacity of 21.5 amps 1) What size OCPD is required for this equipment per Listing and Labeling 2) Am I permitted to put in a lower OCPD than the Max Listed and Labeling on the equipment.

Pete Mazzagatti



Hey Pete thanks for your question. If the AC nameplate states 35 ampere maximum size overcurrent protective device that is the maximum size. A smaller size is not necessarily prohibited but it might not allow the AC unit motor to start. It must be capable of carrying the starting current of the equipment as stated in 440.22(B).

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