You're probably not missing anything [Linked Image] Big A.

What Iwire and I are talking about is that the nameplate on the side of the metal enclosure of the condensor will call out whether only fuses, only HACR type circuit breakers or either can be used to provide the overcurrent protection for the machine. We always read the nameplate to get the numbers for the min. circuit ampacity and the maximum overcurrent protection (OCP). . .the wording on that label may vary from model to model when it describes the OCP types the manufacturer allows.

Much of the time, as you are describing, the condensing unit will allow protection by HACR type circuit breaker, and that breaker can be in the service center with a simple unfused pull out disconnect outside at the AC condensor. However, the manufacturers wording on the AC condensor must agree with what you do. Read the nameplate closely to comply with 110.3(B).

The 2002 NEC Handbook has a great example (Exhibit 440.1) of the possible hookups after 440.21.

Al Hildenbrand