A Tucson home inspection leaves the AC mostly untested

The standard the inspector works to

Home inspectors in Arizona work to the AZ ASHI Standards of Professional Practice, the October 27, 2023 edition the state adopted in May 2024. Section 10 covers central air conditioning: the inspector looks at the equipment, the controls and the ducts, and runs the system with its normal controls. Section 10.3 then lists what the inspector is not required to do. Two of those lines decide a lot on a Tucson resale. The inspector does not have to

"operate cooling systems when weather conditions or other circumstances may cause equipment damage"

or "observe the uniformity or adequacy of cool-air supply to the various rooms".

The general limitations go further and call the whole inspection "not technically exhaustive." That's fair to the inspector, who covers the roof, the wiring, the plumbing and everything else in one visit. The AC is one section of that report.

The readings a general inspection leaves out

There is no refrigerant pressure, capacitor, amp-draw or temperature-split test anywhere in that standard. In practice a general inspection doesn't measure:

• refrigerant charge
• static pressure in the ducts
• amperage draw on the compressor and the fan motors
• duct leakage
• how much life the equipment has left

Then there's the weather line. Running a compressor in the cold can damage it, so one Tucson inspection firm states it doesn't run cooling when it's under 65 F outside. Close on a house in January and your report may describe an air conditioner that nobody switched on.

Older houses, second and third systems

In Pima County, 54 percent of homes were built before 1990, and the median year built is 1988 (Census ACS 2024). Many resale houses here are on their second or third system, and the seller often can't say when the current one went in. A local contractor puts typical Tucson lifespans at 12 to 17 years for central AC and 10 to 15 for heat pumps, so a unit that cools fine on inspection day can still be near the end of its run.

Age is one question. Size is another. Replacement systems in older houses are often sized by square footage instead of a Manual J load calculation, and a system that's oversized for the house short-cycles, wears its parts faster and leaves some rooms warmer than others. When the readings point that way, I say so in the report.

Ten days, then the BINSR

Section 6a gives you 10 days by default. The contract was revised in February 2026 (Rev. 02/26) and the ten-day default did not change. Before they run out you deliver the BINSR, the Buyer's Inspection Notice and Seller's Response, listing the items you disapprove of. Agent explainers say the seller typically has five days to respond.

Section 5a gives an AC finding its weight. The seller warrants that the heating and cooling will be in working condition at the earlier of possession or close of escrow, so a finding on your BINSR points at something the seller has already promised.

Inside the window

The home sale inspection page lists everything I check and the price per unit.

Questions buyers ask