Some problems with your air conditioner are easy to fix. You might only need to replace the air filters or wash down your exhaust system, which can easily be resolved by the help of our AC service in Janesville, WI.

Common Reasons Why Your AC Is Blowing Warm Air

Here are a few of the most common reasons why your AC might be blowing warm air:

  1. Thermostat Issues: If your home or office air conditioner is blowing heated air, the first thing to examine is the thermostat. Ensure that the thermostat is set to COOL and the fan is set to AUTO. And, of course, the set temperature is cooler than the ambient temperature.

  2. Clogged Air Filter: A dirty, clogged air filter can obstruct airflow and, in extreme cases, completely prevent air from getting into your AC system. Check and consider replacing your air filters regularly to avoid this problem.

  3. Low Refrigerant: Low refrigerant is the most likely reason AC blows warm air. If your air conditioner isn’t cooling, the refrigerant may be starting to leak, and what’s left isn’t enough to keep your home cool.

  4. Faulty AC Compressor: A faulty compressor will halt the entire cooling process of your air conditioner. AC compressors can fail due to various factors, such as electrical problems or overheating. If you suspect the compressor fails, you should seek the advice of our experienced HVAC technician for an AC tune-up in Janesville, WI.

  5. Dirty Air Ducts: Look for shut or blocked return air vents around your home. Closing air vents in your home prevents airflow from entering the room, but it can also end up causing an imbalance in your whole duct system.

    Examine the return air vents for any visible broken or separated ductwork. These issues can also disrupt airflow within your home’s ductwork.

  6. Lack of Power to the Outdoor Unit: An indoor evaporator or air handler device and an outdoor condensing unit are common components of air conditioning systems. If the air handler is operational, the fan will continue to blow air into your space. However, without a properly functioning condenser unit, there will be no cooling, resulting in your air conditioner blowing warm air.

  7. Air Duct Leaks: A recent construction project may have damaged your home’s ductwork, or birds or rodents may have made their way into your ductwork.

    Leaks in your ductwork allow cool air to escape while drawing hot air from your attic. Check for any holes, cracks, dents, twisted or disconnected ducts, or other types of damage if you have access to your ductwork.

  8. Frozen Evaporator Coil: Frozen evaporator coils are another cause of your home’s air conditioner blowing warm air. These refrigerant-filled coils absorb heat from the air like a sponge. The evaporator becomes too cold without adequate airflow, resulting in ice buildup. When this happens, your unit will emit warm or no air. Warm air must circulate the coils for them to function properly.

  9. Fan Problems: There are several reasons your AC unit’s fans aren’t working properly. A faulty motor, worn belts, or lubrication could all be to blame. Dirt and debris can also wreak havoc on the fans. If the fan on the indoor or outdoor unit fails to function properly, poor airflow will result. As a result, your air conditioner will blow warm air rather than cool air.


For AC service in Janesville, WI, contact Arch Inc. We have 30+ years of experience in the HVAC industry and always deliver beyond satisfactory service. You can call us at (608) 362-4090.