An air conditioner does not stop working simply because Tucson reaches 110 degrees. It does, however, operate with less margin for dirty coils, weak electrical parts and poor airflow. Extreme heat tends to reveal problems that were already developing.
The outdoor unit has a harder job
The condenser must release heat into air that is already very hot. Dust, cottonwood, weeds and monsoon debris on the coil make that process harder. Keep the area around the unit open, but do not blast the cabinet with high-pressure water or spray electrical compartments.
Longer run time can be normal—up to a point
On the hottest afternoon, a properly operating system may run for long periods. Trouble is more likely when indoor temperature continues climbing, airflow changes, the breaker trips or the equipment begins making a new sound. Compare the system to its own past performance under similar weather.
Electrical parts often fail at startup
Capacitors, contactors and motors experience repeated heat and cycling. A weak part may hum, click or take several tries to start. Do not keep cycling power from the thermostat or breaker. One reset is enough; a repeated fault needs testing.
Airflow problems compound in the heat
A dirty filter, blocked return or blower issue reduces the amount of heat carried back to the indoor coil. The coil can ice even when the weather outside is extremely hot. If you see ice, turn cooling off and do not scrape it.
Prepare before the forecast turns red
Use AC maintenance for a working system or AC repair for an active problem. Call 520-303-3220 .