Installation and replacement. The company you're matched with sizes a new
system from a load calculation on the house, not the tonnage on the old nameplate, and quotes it
in writing before anything is ordered. South Tucson is in the City of South Tucson, so its permit rules apply rather than the City of Tucson's; the contractor confirms them and pulls the permit. Fitting new equipment into an older house can mean new ductwork, moving a roof unit to the ground, or ductless mini splits, and the right answer depends on the walls, roof and electrical panel. If TEP is your utility, ask whether the company you're matched with is a participating contractor in TEP's Efficient Home Program, which pays instant rebates as listed by TEP in October 2026.
Heating. At about 2,430 feet, South Tucson is valley-floor desert where Pima County's code winter design temperature is 35F, so heating duty is light. A heat pump is the sensible default here: the area needs about 2.6 cooling degree days for every heating degree day, so the same unit does the cooling you need anyway.
Maintenance. A tune-up before the first 100F day covers the coils, refrigerant
charge, electrical connections, capacitor and condensate drain, and a second look after the
monsoon clears the dust. Older homes may carry an evaporative cooler alongside refrigerated air, so a maintenance visit can cover both, and leaky older construction lets in more dust.
Check any contractor's license with the Arizona Registrar of Contractors at roc.az.gov. Residential air conditioning and heating work falls
under the R-39 class. The service pages below go straight to the job you need.