Inspected a home today that had a 50 AMP circuit breaker for the Air conditioner but it only had 10 Gauge wire connected to it. The air conditioner label indicated a minimum amp rating of 28 amps and stated to use a maximum 50 amp circuit breaker. The unit is located about20 feet away from the panel but the wires run inside the walls so the actual wire run would be more like 30 feet.
I know there are instances where a smaller wire can be used. Does this sound like one of those instances?
Yes, the #10 AWG conductors are fine with the 50 amp OCPD. The wire is sized based on the MCA or minimum circuit ampacity. The Maximum OCPD size is only needed for short circuit and ground fault protection. The overload device within the unit will protect the conductors from overload.