I just went bact to the OP's post. I quote: "Hi, I'm the OP. Yes, the mini split a/c system specs explicitly call for a 50amp breaker and #6 AWG (although I shudder to think that it'll actually use that much, with a 16 SEER)."
What does the code say about over-protecting a cable? The cable is protected by a 50 amp breaker. Going by "general code" you cannot run an AWG10 circuit on a 50 amp circuit. What specifics outside of the "general code" would allow the cable to be protected with an over-rated protection device? And yes, the air conditioner in my house is connected with stranded flexible conductors from the house to the outside unit - run through weatherproof flexible conduit to the "protected disconnect" - a weatherproof single circuit circuit breaker enclosure. The outdoor unit sits on a plarform of concrete blocks on a base of concrete patio stones, and is not bolted down.. Been that way for over
40 years. (except the original unit sat right on the patio stones, I raised the unit on concrete blocks to keep it out of the dirt and leaves when I had the unit replaced.