Advice written for Phoenix does not transfer cleanly to Tucson. The city sits roughly 1,300 feet higher, its winter nights get properly cold, and a large share of older Tucson homes were built around evaporative coolers rather than refrigerated air — equipment that works well in dry June heat and struggles once monsoon humidity arrives.
So the question here is often not just "who can fix my AC" but "what should this house actually be running". We looked at the Tucson companies with the strongest reputations and chose one, with two alternatives listed below.