cooling system for a reason! Nonetheless, warm air emitting from air conditioners is more common than you might think. The root of the problem may be as simple as operator error, or it could be something much more cost-intensive, like the need for a full HVAC system replacement. Ask yourself these questions to determine what’s causing your AC unit to blow warm air.

1. When was the last time I changed the filter?
Filter cleaning and replacement are major aspects of proper routine maintenance. You should change your air filter at least monthly – and more often if you have an allergy sufferer in your home or if the air quality outside is particularly bad.

A dirty air filter is enough to clog your AC condenser coils. Dust and debris build-up and prevent the condenser coils from working properly to cool the incoming air. So while your air conditioner is still technically functioning, the air it’s blowing is warm.

2. How’s my Freon level?
If your AC unit is low on refrigerant, the outdoor unit stops running. In some cases, the fan continues working, but the air emitting from the air conditioner is hot.

You should check your Freon levels at the beginning of the season and keep an eye on them throughout the summer. If your refrigerant levels are low at any point, you may need a Freon recharge. Do not perform this by yourself, as Freon is a dangerous chemical and should only be handled by trained professionals. And because low refrigerant levels are often indicative of a bigger problem, such as a leak, call an HVAC service technician if you notice your AC unit is running low on Freon.

3. Have I checked the condenser coils?
As previously noted, a dirty air filter may result in condenser coil clogs. But it’s not always the air filter’s fault. Your AC unit is outdoors, so it makes sense that dirt and debris get into the unit. If this happens, the condenser coils become clogged and are unable to cool the outdoor air. Since all the other components are working properly, the air conditioner is still blowing, but the outgoing air is warm.

Cleaning the condenser coils is a vital part of any routine maintenance plan. You should be checking on the coils regularly. If they need to be cleaned, call an HVAC service specialist. Cleaning the condenser coils is potentially dangerous and should be handled by professionals. Alternately, get an HVAC service plan so routine maintenance is covered in prescheduled visits and you don’t need to scramble for a last-minute servicing.

4. Is my thermostat on the wrong setting?
This may seem silly, but it happens often. Depending on your thermostat placement, it’s easy to bump into the unit and change the setting. You don’t realize the setting has been changed until you feel a temperature difference in your home.

Double-check your thermostat to make sure it’s set to the right temperature and on the right setting (heat/cool). If the setting is correct, perform a quick test: Drop the temperature lower and see if the system kicks on. Feel the air coming out of the vents. If it’s cool, your system should be working, although it may need a tune-up. If the air coming out is warm, call an HVAC service technician right away.

5. Did I get a seasonal tune-up?
Your HVAC system requires regular maintenance, but it also needs a full tune-up at least once per year. Your tune-ups should always be preemptive. Service your air conditioner in the spring in anticipation of the summer, and if possible, service your furnace in the fall before the weather cools down.

If you didn’t get a seasonal tune-up on your AC unit this spring, your HVAC system is likely suffering. Tune-up tasks include cleaning ducts and vents, repairing damage, checking electrical connections, and removing the problematic build-up of debris. Without these necessary tasks, your system is unable to perform efficiently, in which case the warm air blowing out of your air conditioner is not your only concern.

Invest in an HVAC service plan so you don’t need to worry about keeping up with maintenance ever again! A plan covers your seasonal and routine services, and you’re rewarded with special insider discounts to boot.

You want your family to be kept cool and comfortable, so it’s frustrating when your air conditioner starts blowing hot air. Especially in the sweltering heat, your home should be a cool retreat. If your home cooling system isn’t offering you any relief from the heat outside, it’s time to diagnose the problem and fix it.

If you’d like help diagnosing and treating problems with any of your HVAC systems, contact the On Time Experts.

Meet the Author
Randy Kelley
Randy Kelley


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