Air Conditioner Blowing Warm Air: Is The Condenser Faulty?

Posted on: 17 August 2023

Some air conditioner faults can be difficult to detect, but if your air conditioner is blowing warm air, you will probably notice very quickly. If your air conditioner has suddenly turned into a furnace, the problem may be caused by issues with the system's condenser. 

What Do Air Conditioning Condensers Do?

Air conditioners create cool air using refrigerant liquids, which absorb heat from the air as they pass through your system's indoor blower unit(s). This absorbed heat needs to be released before the refrigerants can be reused, which is where the condenser comes in.

The condenser is installed outdoors, usually in the same housing as your system's compressor. It contains a series of heat exchanger coils, which extract heat from the refrigerant liquids. The heat is then expelled from the unit by a large, powerful fan.

If the condenser is not functioning properly, it may not be able to extract heat from the refrigerant liquids. If refrigerant is still warm when it is returned to the indoor unit(s), it will heat the air surrounding the indoor unit(s), instead of cooling it. Your air conditioner will start blowing warm air, and your home will probably become stiflingly hot. 

Why Is Your Condenser Malfunctioning?

Condensers can suffer from a number of problems that prevent them from extracting heat from your air conditioning system. Here are some of the most common faults:

Broken Fan Blades

Condenser fans are installed inside protective housings, but they are not immune to physical damage. Large sticks and branches can shatter fan blades if they fall through the fan's protective grille. If the housing is damaged, animals may also crawl inside looking for shelter — if they are still inside when the fan starts up, things can get pretty gruesome, and the fan can be badly damaged.

Faulty Fan Motor

If the condenser's fan blades seem to be in good condition, but the fan itself isn't rotating when the system is active, its motor may be faulty. The electric motors that power condenser fans have a limited service life, and will burn out after years of use. Fan motors are more likely to burn out if your system is in constant use or if the fan's air filters are clogged with debris.

Worn Fan Bearings

If the condenser fan spins, but makes a loud rattling or grinding sound, its bearings may have worn out. These bearings reduce friction and prevent the fan from overheating, but they also have a limited useable life. Worn fan bearings can prevent the fan from spinning quickly enough, or cause it to wobble while it spins — both problems can impair the fan's ability to expel heat.

What Should You Do If Your Air Conditioner Is Blowing Warm Air?

Before you do anything, you should check your system to make sure it isn't set to blow warm air. Some air conditioners have reverse cycle functionality, which allows them to function as heaters during cold weather. If your air conditioner system is a reverse cycle system, it may simply have been set to heating mode accidentally.

If your system is set to cooling mode or lacks reverse cycle functionality entirely, you should call in a professional air conditioning repair service as soon as possible. Trained technicians will thoroughly inspect the condenser, and will also check for other problems that can cause air conditioners to blow warm air (such as frozen evaporator coils).

If the fault lies with the condenser, the malfunctioning component(s) can usually be repaired or replaced quickly and inexpensively. If your system is very old, it may be more economical to have it completely replaced. Make sure to ask your repair service for advice and recommendations.

For more information on air conditioning repair, contact a professional near you.