When you turn on your home’s AC, you expect nice, cold air to come from your vents. If that doesn’t happen, it’s natural to wonder: why is my AC blowing warm air? Before you panic, however, it’s important to realize that the problem isn’t necessarily major. Here are some of the reasons an AC might start blowing warm air.
Incorrect Thermostat Settings
One of the most frequent causes of an AC blowing warm air is incorrect thermostat settings. It’s easy to accidentally set your thermostat to heating mode without realizing it. So, if your AC starts blowing warm or hot air, check your thermostat first.
A Dirty Air Filter Can Restrict Cooling
The next most frequent cause of an AC blowing warm air is a dirty air filter. Most central ACs have air filters that require replacement every 90 days of use. If you neglect to change yours, it can accumulate enough dirt to restrict airflow through your AC. When that happens, your AC can’t effectively extract heat from your home’s air. If your AC starts blowing warm air, check whether the filter needs replacement. If so, replace the filter with one that has the same dimensions and MERV rating.
Low Refrigerant or Refrigerant Leaks
A more serious cause of an AC blowing warm air is refrigerant loss. When your AC loses refrigerant, the immediate effect may be the opposite of what you expect. Initially, the air coming from your AC may blow colder. That happens because low refrigerant pressure causes air conditioning systems to run at abnormally low temperatures. However, when the pressure falls enough, one of two things happens. Your AC’s evaporator coil can freeze, preventing airflow and adequate heat transfer. Or the system’s cooling capacity can drop so low that it can no longer meet your home’s cooling demand.
If you hear your AC making any hissing noises near its indoor or outdoor units, suspect a refrigerant leak. Or, if your outdoor unit makes more noise than usual, it may be a compressor issue. That’s a likely outcome of refrigerant loss. If you hear such sounds, turn off your AC immediately to prevent further damage.
Outdoor Unit Problems or Dirty Coils
Problems with your AC’s outdoor unit can also cause it to blow warm air. One problem is when the condenser coil in your outdoor unit gets too dirty. That can hamper your AC’s ability to expel heat to the outdoors. That would raise the overall refrigerant temperature and cause warm air to come from your vents. If you suspect a dirty coil, turn off the power to your AC and try rinsing the coil with a garden hose. Only do so with your hose set to a low-flow setting. Otherwise, contact us for a maintenance visit so that we can do the job for you.
Two other problems that can occur in your AC’s outdoor unit are failed capacitors or contactors. Either can prevent the large fan in the outdoor unit from turning on. Without that fan, the outdoor unit can’t remove heat from the system’s refrigerant. Neither is a problem you can remedy, so seek professional help.
When Warm Air Means You Need Professional Repair
There are only two causes of warm air coming from your AC that you can fix yourself. One is incorrect thermostat settings. The other is a dirty air filter. And while it’s sometimes possible to remedy a dirty condenser coil with a quick garden hose rinse, results may vary. In all other cases, it’s wise to schedule service from a qualified HVAC technician. Doing so is especially vital if you suspect that your AC has a refrigerant leak. Continuing to run your AC in that condition can destroy the system’s compressor. That requires a costly repair or, potentially, a complete system replacement.
Schedule HVAC Services With Beeline
If your AC starts blowing warm air and you can’t figure out why, turn to Beeline Heating and Cooling for help. Our team of HVAC technicians is background-checked, well-trained, and insured. They have the skill to repair ACs of all makes and models. To prevent AC failures, we offer a convenient maintenance plan. We also provide 24/7 emergency services if your AC starts blowing warm air outside of our regular hours. Additionally, we offer upfront pricing, so you always know what you’ll pay before we perform any work.
For a quick solution to your AC’s warm air issues in Ames, contact Beeline Heating and Cooling immediately.
