HVAC · fix it
Ac blowing warm air? Here's what to do first
Work the free checks in order — thermostat mode, filter, breaker, outdoor unit, frozen coil — then stop. Refrigerant and electrical repairs are licensed work.
DIY with caution
Doable for a careful homeowner — read the safety note first and stop if anything doesn't match what you see.
Beginner About 25 min
Never open the sealed refrigerant system or the electrical disconnect. Refrigerant handling requires EPA certification in the United States.
Video: Key Fob Rob (YouTube)
What to do, in order
- Step 1: Confirm the thermostat is set to COOL and the setpoint is below room temperature.
- Step 2: Replace a dirty filter; restricted airflow is the most common cause.
- Step 3: Check the breaker for both the air handler and the outdoor condenser.
- Step 4: Look at the outdoor unit: the fan should spin and the cabinet should be clear of leaves and grass.
- Step 5: If the copper line is iced over, shut the system off and run the fan only until it thaws, then retest.
- Step 6: Still warm after a thaw and a clean filter? That points to refrigerant or a failed component — call a licensed HVAC tech.
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