Flo-Aire Heating, Cooling & Electrical

Why Is My Air Conditioner Blowing Out Hot Air?

Even if you’re proactive and consistent about caring for your household air conditioner, problems may sometimes arise with the appliance. Of all the potential issues, few are more noticeable or frustrating than having your AC unit start blowing hot air. Not only does that make for a very uncomfortable home during the Michigan summer, but it’s also a clear indicator that your cooling system is experiencing an underlying mechanical problem.

As a homeowner, having a better understanding of your air conditioner helps equip you to properly respond when the appliance is under the weather. When it comes to an AC unit blowing hot air, there are several possible reasons why it may be happening. Here, we’ll take a look at the most likely causes of this common AC issue and provide you with a few troubleshooting techniques that might just remedy the unpleasant situation.

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5 Common Reasons
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    1. Clogged Air Filter

    One of the most common causes of an AC unit blowing warm air is a clogged or dirty air filter. Whenever your air conditioner is cycling, its filter is trapping airborne contaminants like dust, mold spores, and pollen. Eventually, enough particles will become trapped to clog the filter, which results in the cooling system’s airflow becoming obstructed. When that happens, it can cause a variety of issues for the appliance, including the evaporator coils freezing. With frozen evaporator coils, your air conditioner won’t be able to effectively cool down the air, which can cause warm or even hot air to be distributed around your home.

    If your AC unit starts blowing warm or hot air, replacing the air filter is always a wise troubleshooting technique to try first. Ideally, you should be changing your HVAC air filters regularly to keep the system running smoothly and efficiently. Depending on the type of filters you use, their MERV ratings, and several household factors, you should be replacing your filters every one to three months.

    2. Malfunctioning Thermostat

    Your home’s thermostat has a direct impact on whether cool or warm air is cycled around your living space by your HVAC system. When the thermostat is functioning correctly and properly calibrated, it will direct your AC unit to blow cold air whenever the household temperature is warmer than you want it. However, if the thermostat is malfunctioning or set improperly, it may result in warm air circulating when it should be cold air instead. Typically, older thermostat models are more likely to have problems than modern programmable units.

    When your home’s cooling system is blowing hot air, it may be as simple as adjusting the settings on your thermostat to fix it. However, you may need to have local HVAC professionals recalibrate it, and in some cases, you may even need to replace it entirely.

    3. Refrigerant Leak

    Your air conditioner uses refrigerant to remove heat from oxygen before it’s redistributed around your home. Refrigerant is integral to the cooling and dehumidification of the air, and without it, your AC unit would simply be cycling warm air at all times. So, if your cooling system gets low on refrigerant, it typically prevents the appliance from effectively removing the heat from your indoor air. When this happens, it’s usually because refrigerant is somehow leaking from the AC unit.

    When your air conditioner has a refrigerant leak, simply replacing the lost refrigerant won’t solve the problem. The issue also won’t resolve itself. You’ll need to have the source of the leak located and repaired by trained HVAC professionals. Otherwise, your AC unit will continue to blow hot air, and other equipment problems may arise as well. If you suspect that your cooling system is low on refrigerant, you’d be wise to shut off the system and schedule an inspection as soon as possible.

    4. Dirty Condenser Coils

    Your air conditioner’s condenser coils are part of the system’s outdoor unit, and they have the important role of expelling heat from your home after the evaporator coils remove it from the air. However, because the condenser coils are part of the AC’s outdoor unit, they’re exposed to the elements as well as the accumulation of dirt, grime, and debris. Eventually, if you don’t make a point to regularly clean the outdoor unit and surrounding area, the system’s heat transfer process can be impeded. As a result, your air conditioner may start blowing air that’s warm or hot rather than cold. A dirty outdoor unit can also put extra strain on your cooling system as a whole, worsening its efficiency and increasing the likelihood of mechanical problems.

    It’s always prudent to clean your AC’s outdoor unit periodically. And if your cooling system starts blowing warm air, it’s worth checking to see if the condenser coils may be dirty or surrounded by dirt, leaves, and debris. If so, taking the time to clean the area may be effective for solving the issue.

    5. Leaky Ductwork

    Whenever your AC unit is circulating cool air, that air must pass through your household ductwork before it can flow through your air vents and into your living space. However, your air ducts can sometimes develop leaks, which can result in a variety of issues. In some cases, a consequence of duct leaks can be your cooling system distributing warm air. If there are cracks, gaps, or other openings in the ductwork, then it’s possible for warm air to seep into those leaks and mix in with the conditioned air from your AC unit. As a result, the temperature of the air will be significantly warmer when it flows out of your vents.

    Having dirty or leaky air ducts can have a variety of other negative effects as well, such as poor air quality, mold growth, worsened HVAC efficiency, and many more. That’s why it’s so important to schedule regular duct cleanings. That way, a ductwork professional will remove the contaminants from your air ducts and inspect for any leaks or damage. Then, you can have those problems repaired before they cause too many frustrating issues.

    Southgate's Trusted HVAC Professionals

    If your AC unit is blowing hot air and you’ve been unable to troubleshoot the issue, you can always give us a call at Flo-Aire Heating, Cooling & Electrical. We’ve been proudly serving the Metro Detroit and Downriver area with expert HVAC services since 1955, and our team will get to the bottom of your air conditioning issues. If you’d like to learn more about our services or schedule an appointment, give us a call today at (734) 285-1809.

    Flo-Aire Heating, Cooling & Electrical, Inc.

    Flo-Aire Heating, Cooling & Electrical, Inc.

    Locally owned and operated in Southgate, MI since 1955, Flo-Aire Heating, Cooling & Electrical is one of the top heating & cooling companies in Southeast Michigan. Flo-Aire provides residential, commercial and industrial HVAC services throughout all of Metro Detroit.

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