ac blowing warm air

AC Blowing Warm Air? Here’s What Might Be Wrong

According to the U.S. Energy Information Administration’s 2022 report, nearly 90% of American households rely on air conditioners to stay cool.

So, when you find your AC blowing warm air instead of that refreshing breeze, it can quickly become frustrating, especially on a scorching day.

Whether it’s a minor DIY AC repair or a more complex issue that requires professional help, understanding the cause of the problem is key.

Identifying the problem early can save you time, money, and discomfort.

Keep reading to learn more.

Incorrect Thermostat Settings

Before assuming the worst, check your thermostat settings.

If the AC is set to “heat” instead of “cool,” it will blow warm air.

Also, ensure the fan setting is on “auto” rather than “on.”

When the fan is set to “on,” it runs continuously, even when the compressor is off, which can cause warm air to circulate.

Dirty or Clogged Air Filter

A dirty air filter blocks airflow, so the AC struggles to push cool air through the ducts.

Changing or cleaning the filter every one to three months helps prevent this problem and improves performance.

Refrigerant Leak

Low refrigerant levels can prevent your AC from cooling correctly.

Refrigerant leaks can occur due to worn-out components or damage to the refrigerant lines.

Signs of a leak include:

  • Hissing sounds
  • Frozen evaporator coils
  • Reduced cooling performance

Since handling refrigerant requires special certification, contact a professional to locate and repair leaks.

Dirty Condenser Coils

The outdoor unit’s condenser coils release heat absorbed from inside your home.

If the coils are covered in dirt, they cannot function efficiently, causing your AC to blow warm air.

Follow these steps to clean the coils:

  • Turn the power off
  • Locate the condenser unit (the large metal box with a fan on top)
  • Clean the area around the unit and brush off dust and dirt
  • Spray the coils with water from the inside out (opposite the airflow direction)
  • If your coils are very dirty, you may want to use a coil cleaner
  • Check for bent fins that can block airflow
  • Reassemble the unit and test

Electrical Issues

Electrical failures, such as a tripped breaker or a blown fuse, can disrupt your AC’s ability to cool.

Check your circuit breaker if the outdoor unit is not running while the indoor fan is on.

Reset it if necessary, but it may need professional attention if the breaker trips repeatedly.

Faulty Capacitor or Compressor

The capacitor helps start the AC’s compressor, which is responsible for cooling the air.

A faulty capacitor can stop the compressor from running, leading to warm air output.

Similarly, a damaged compressor may struggle to circulate refrigerant properly.

A technician can diagnose and replace these components if needed.

Frozen Evaporator Coils

If the evaporator coils freeze, they cannot absorb heat, leading to warm airflow.

Frozen coils often result from:

  • Restricted airflow
  • Low refrigerant
  • Malfunctioning blower fan

Turn off the AC and let the coils thaw entirely before restarting.

If freezing persists, consult a professional for AC troubleshooting.

Blocked or Leaky Ducts

Ductwork issues can cause your AC to blow warm air.

Leaky ducts let cooled air escape before reaching your rooms, while blockages restrict airflow.

Inspect visible ducts for leaks or damage and seal them using duct tape or mastic sealant.

If airflow remains weak, professional duct inspection may be necessary.

Malfunctioning Expansion Valve

The expansion valve directs the flow of refrigerant to the evaporator coils.

If it malfunctions, it may not provide the correct amount of refrigerant, leading to cooling issues.

Since this component is complex, professional diagnosis and repair are recommended.

Defective Blower Motor

The blower motor pushes cooled air through your home’s vents.

If the motor fails, air may not circulate properly, making it feel like your AC is blowing warm air.

Unusual noises, weak airflow, or a complete lack of air movement indicate a potential blower motor issue.

AC Maintenance Tips to Prevent Warm Air Issues

Regular AC maintenance prevents problems and keeps your system running efficiently.

Here are some essential maintenance tips to consider:

  • Replace filters every one to three months to maintain airflow and efficiency
  • Clean off any dirt and debris from the outdoor unit to prevent overheating
  • Inspect refrigerant levels, as low levels may indicate a leak that needs professional repair
  • Check ductwork for leaks or blockages that could reduce airflow
  • Schedule professional inspections to find potential issues early

When to Call a Professional

Although some common AC problems can be fixed with a DIY repair, others may need professional expertise.

Here’s why:

  • Professionals can quickly identify the root cause, whether it’s a refrigerant leak, electrical issue, or compressor failure
  • DIY fixes can sometimes make things worse; technicians are properly equipped to fix any issue correctly
  • Handling refrigerants or electrical components without proper training can be dangerous
  • A well-repaired AC runs efficiently, preventing further damage and extending its lifespan
  • Misdiagnosing the problem can lead to costly mistakes

Finding the Best AC Repair Service

Finding a reliable AC repair service in Mesa, Scottsdale, Phoenix, and surrounding areas is crucial for ensuring your system operates efficiently during the intense Arizona heat.

Here’s how to do it:

  • Check online reviews on Google, Yelp, and Angi for customer feedback
  • Get recommendations from friends or family based on their experiences
  • Compare quotes from multiple providers to find fair pricing
  • Choose a company with a good track record and expertise in your AC system type
  • Check credentials to ensure the company is licensed and insured in Arizona

What to Do About an AC Blowing Warm Air

If you have an AC blowing warm air, addressing the issue immediately is crucial to avoid further complications.

Whether it’s something simple or a more serious problem, identifying the cause will help you decide whether it’s a DIY fix or a job for the professionals.

Mark Daniels Air Conditioning & Heating in Mesa offers swift, efficient, and high-quality service, ensuring any problem is addressed correctly the first time.

Whether it’s an air conditioning or heating issue, we promise to do it right, on time, and at a fair price.

Contact us today for the best service experience you’ll ever have!

Looking for a Mesa Emergency Air Conditioning Company?
Choose Mark Daniels Air Conditioning & Heating for expert emergency HVAC services. We’re committed to delivering fast, reliable service to keep your home cool and comfortable, even in urgent situations.
Call (480) 571-7219 or request service online now!