1 — Look at the Settings — Sometimes human error when adjusting the unit’s settings will cause the system to blow out hot air. Make sure the selector switch is on cool and not heat. When the switch is set to heat, the unit automatically starts producing warm air. Simply move the switch back to the cool setting and the unit will start producing cool air.
2 — Inspect the Compressor and the Condenser — If you have verified that the selector switch is in the correct position, start looking at the compressor and condenser, which are components of the outside unit. Make sure the power supply to the exterior of the building is on.
If the power supply is interrupted, only the inside handler will function and the air is not cooled. Make sure the airflow is unobstructed. Make sure there is no dirt, dust and debris clogging the condenser coils. Dirty condenser coils interfere with the proper function of the air conditioner. You should periodically clean the system’s condenser coils during the summer for maximum efficiency.
3 — Inspect the Air Filter — A clogged air filter alone is sometimes not the main reason an air conditioner is blowing hot air but it can compromise its performance. Air filters are inexpensive and almost anyone can easily remove the dirty one and install the clean one in just a few minutes.
Failing to replace the filters or clean them regularly will cause dust to clog up the system’s condensing coils. Dust can also end up inside the home, which is a health risk because it can lead to allergic reactions, asthma attacks, colds and other upper respiratory ailments.
4 — Check the Refrigerant — If there is a leak or the compressor is malfunctioning, the system will lose refrigerant and can no longer cool air. The refrigerant charge is reduced and interferes with proper function.
Sometimes a sign that the AC system needs refrigerant is ice formation on the inside and outside unit condensers. This is a repair best handled by AC professionals. The repair is typically inexpensive unless you need to replace the compressor.