AC Blowing Warm Air: What It Can Mean

What to check when your air conditioner is blowing warm air, from thermostat settings and airflow to outdoor-unit and refrigerant-side problems.

Warm air from the vents can be caused by a simple setting or by a problem that needs HVAC diagnosis.

Quick checks

• Thermostat is set to COOL rather than FAN
• Filter is not badly clogged
• Outdoor equipment has power
• Registers are open

Possible service causes

A failed outdoor fan, electrical component fault, compressor issue, refrigerant-side problem, frozen coil, or control fault can all prevent normal cooling. Refrigerant work should be handled by qualified HVAC personnel.

See AC repair if these basic checks do not restore cooling.

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