Why Is My Air Conditioner Blowing Warm Air?

It’s hot outside, and you come home expecting a pleasant rush of cool air, as you open the front door. But there is no rush of cool air. You check the air flow from the vent, and it turns out that your air conditioner is blowing warm air. There are several common causes behind this type of problem with air conditioners. Some of which have an easy fix, and some of which will require a serviceperson.

Thermostat Settings

The setting of the fan, may affect the temperature of the air your AC is pumping out. This is the mechanism that circulates air through your home. Most AC experts recommend that you set the fan to AUTO rather than to ON. On AUTO, the fan will only come on when the air conditioner itself is activated. In other words, if the air conditioner is not running, neither is the fan. If the fan is set to ON, it will blow warm air through your house when the air conditioner isn’t activated. Make sure the fan is set to AUTO before resorting to a repair call.

Dirty Air Filters Restrict Air Flow

Air Filter

Air filters are used to protect your system from contaminants, like pet hair and dust. When the filter gets dirty, it restricts air flow to your unit. One of the results can be the circulation of warm air instead of cool air. Check manufacturer guidelines to find out how often to change (or clean) your filters. If your air conditioner is blowing warm air, experts recommend that you change out the filter before you call a repairman.

Dirty Coils in the Outdoor Unit

The coils on your outdoor unit can develop a buildup of dust and pollen. If the coils are dirty, then the outdoor unit can’t do its job correctly and one of the results will be your air conditioner blowing warm air. Good technicians will always take the time to clean off the coils in your outdoor unit when servicing it during the summer. You can clean the coils off yourself with a hose running gentle water (there is no need for a high-pressure sprayer).

Restricted Airflow to the Coils in the Outdoor Unit

The coils in your outdoor unit need to have plenty of airflow around them. For that reason, you need to keep all shrubs and plants at least a few feet away from your outdoor unit. plants on a houseDuring the summer months, plants can grow pretty quickly and begin to cause restrictions in air flow. Preventing your system from properly cooling the air being blowing through your home. Check to make sure that bushes or shrubbery aren’t causing airflow restriction.

Outdoor Unit Not Receiving Electricity

You should also make sure that your outdoor unit is actually getting electricity. It is possible for the indoor unit to be running while the outdoor unit is off. The fan will circulate warm air, in the event that the outdoor unit isn’t functioning. If you find that the outdoor unit isn’t running, check is the circuit breaker. If the fuse has blown or the circuit breaker has tripped, that would stop the flow of electricity. You should call a technician before trying to turn it back on.

Frozen Evaporator Coil

Frozen Coil

The evaporator coil on your air conditioning unit can freeze into what is essentially a solid block of ice. This blocks the cool air from flowing to the vents and into your home, so your air conditioner will blow warm air. The evaporator coil is supposed to form cold condensation to cool down the air that flows over it on the way to the vents in your home. If the air blowing over the coil is cooler than the freezing point of water (which can happen on hot days if you set the system temperature below 70°F), then the condensation will freeze and form ice. More ice forms until air can no longer flow over the evaporator coils. Causing the unit to blow warm air.
A quick fix is to turn your air conditioning unit off for a few hours to allow the ice to thaw. Your air conditioning system should work properly after that. If it freezes up again, it’s time to call a technician to have your system evaluated.

Low Refrigerant

Refrigerant is used to cool the air in your home by absorbing heat from the air. If there is not enough refrigerant in your system, then it cannot cool the air. Refrigerant leaks are a very common cause of an air conditioning blowing warm air. If your refrigerant is low, a good technician will not only top it off but will also track down and fix the source of the leak.

Leaking Ductwork

leaking ductwork

There is a chance that very hot air from your attic is being pulled into the ducts. This is a strong possibility if there are leaks in your ductwork. Causing the air exiting your vents to be warmer than it should be. Technicians can track down the source of leaks using a smoke-like substance. Then repair them fairly easily.
Call Drew Green Heating & Air

for Fast, Friendly Service

If your Air Conditioner is blowing out warm air instead of cool air, give us a call at Drew Green!

Whether you notice the problem on weekday afternoon or late at night on a weekend, don’t worry — we offer 24-hour emergency service. We also perform tune-ups, preventative maintenance, installation, and repairs for AC systems, furnaces, boilers, and hot water heaters. At Drew Green, we are so confident in our ability to exceed your expectations that if you aren’t satisfied with the repair or installation we perform, we’ll return for free! Contact us today for a free estimate.