Why is my air conditioner blowing warm air?

The most common causes are a clogged MERV-8 air filter or a tripped condensate float switch. A clogged air filter restricts airflow and causes the compressor to shut down, while a full drain pan triggers the float switch to cut power to the compressor as a safety measure.

How do I fix an air conditioner blowing warm air?

Start by replacing the air filter with a new MERV-8 filter and emptying the drain pan beneath the indoor air handler. Check that the thermostat is set to COOL and the temperature is below the current room temperature. Verify both indoor and outdoor circuit breakers are ON. Allow 20-30 minutes for the system to resume cooling.

What is a condensate float switch?

A condensate float switch is a safety device installed in the drain pan of an air conditioner's indoor air handler. When the drain pan fills with water due to a clogged drain line, the float switch rises and cuts power to the compressor to prevent water overflow and property damage.

When should I call an HVAC technician for warm air issues?

Call a licensed HVAC technician if the air conditioner continues blowing warm air after replacing the filter and emptying the drain pan, if you see ice on the coils, if the outdoor unit is not running, if you hear unusual noises, or if you smell burning odors. Low refrigerant and compressor issues require professional diagnosis and repair.

HVAC

Air Conditioner Blowing Warm Air

PropSWOT Team

January 7, 2025

8 min read

Cite This Article

PropSWOT Team. "Air Conditioner Blowing Warm Air." PropSWOT Resources, January 7, 2025. Available at: https://tenant.propswot.com/resources/ac-blowing-warm

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