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Why Is My AC Blowing Warm Air?

Air Conditioning

Thermostat set to heat

Hot summer days are upon us, which means that your air conditioner in Idaho is working hard to keep you cool and comfortable.

If your air conditioner starts blowing hot air through the registers, there could be several causes, including:

Thermostat & Fan Settings

The first thing to check is your thermostat and confirm that the settings haven’t been bumped or toyed with. If your thermostat is set to “heat,” switch it back to “cool.” It’s a simple cause, but it happens more often than you think.

If that doesn’t resolve the issue, check the thermostat fan settings. It should not be set to “on.” This may seem counterintuitive, but turning the fan on will blow air through the ductwork regardless of whether your air conditioner is operating. The right setting is “auto.” When you set it to auto, the fan will only operate when your air conditioner operates. 

Dirty Evaporator Coils

Dirty coils are less efficient and can diminish your air conditioner’s capacity. Cleaning the coils is a simple solution that you can quickly perform.

However, it’s usually best to have a trained HVAC technician do the work as part of a routine service appointment. This will allow the technician to inspect and tune up your system as necessary.

Tripped Circuit Breakers

Other causes of warm air blowing through registers can be a little more complex to correct. It is possible that your indoor or outdoor unit has lost power.

Check your circuit breaker to confirm that it hasn’t tripped. If it has, reset the breaker. If this doesn’t resolve the issue, then you may have a faulty circuit breaker or fuse panel.  

Low Refrigerant

Another common cause of warm air blowing through the registers is that you are low on refrigerant. Often, this is because you have a leak within the system that requires professional repairs.

You should never attempt to recharge refrigerant as this is a specialized task. Refrigerant is toxic, so it is best left to a professional.

Compressor Failure

If your compressor fails, it will fail to sufficiently compress the refrigerant. This diminishes efficiency and reduces the output of cool air. Signs of compressor problems include:

  • Growling or screeching noises
  • Slow AC start
  • Frequently tripped breakers
  • Diminished airflow

If the compressor is the cause of the problem, an experienced HVAC technician can repair or replace the component.

Depend On Advanced Home Services for Your Comfort!

Our NATE-certified HVAC technicians are highly trained professionals who adhere to the strictest safety and quality standards.

We will thoroughly inspect your system and determine the root cause of your cooling issues. We maintain a complete parts inventory and can quickly restore comfort to your home.

Is your air conditioner blowing warm air through your registers? Contact the air conditioning experts at Advanced Home Services at 208-745-9406 for AC repair.

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