Top Causes of AC Blowing Warm Air & Solutions

For over 8 decades, First Call Heating & Cooling has been a pillar of reliability and customer satisfaction in the Portland area. Our technicians are trained to tackle any HVAC challenge you may encounter, and we have a long history of happy customers to prove it. One problem that homeowners often face, especially when using air conditioning in winter is their AC unit blowing out warm air. It’s a common issue that can be both frustrating and uncomfortable. In this article, we’ll shed light on common reasons behind this problem, how to troubleshoot them, and when it’s time to call in the professionals.

Common Causes of AC Blowing Warm Air

Incorrect Thermostat Settings – Sometimes, the issue is as simple as the thermostat being set to “heat” instead of “cool”.
Dirty or Clogged Air Filter – A clogged filter can restrict airflow, causing the system to struggle and blow out warm air.
Refrigerant Leaks – Low levels of refrigerant can significantly impair your systems’ cooling capabilities.
Electrical Issues – Faulty wiring or a malfunctioning capacitor can also be a culprit.
Dirty or Frozen Evaporator Coils – Located in the indoor air handler unit, these coils can become dirty or clogged, restricting their ability to cool the air properly.
Malfunctioning Compressor – If the compressor in your unit is malfunctioning, the refrigerant is unable to turn from a gas to a liquid to cool the air. This is vital in ensuring that cold air blows from your air conditioning vents.
Obstructed Outdoor Unit – Overgrown landscaping or other debris can clog your AC system. Obstructions such as leaves or tree limbs can cause the system to work harder than it needs to, sometimes causing it to overheat.
Tripped Circuit Breaker – Air conditioning systems consume a significant amount of power, making them more likely to trip the circuit breakers in your home. If this occurs, the power needed to cool the air is no longer available, causing the AC to fail to cool the air as intended.

How to Troubleshoot a Blowing Warm Air AC Unit

While many of the problems listed above require a professional HVAC technician, there are a few issues you can troubleshoot and remedy on your own.

Check the Thermostat – Make sure it’s set to “cool” and at an appropriate temperature.
Replace or Clean the Filter – A clean filter provides better airflow.
Inspect for Refrigerant Leaks – Look for any visible leaks, but don’t try fixing them yourself.

Most Common Reasons for AC Blowing Warm Air When Using Air Conditioning in the Winter

Interestingly, using air conditioning in winter can highlight existing problems. Low refrigerant levels or improper thermostat settings can become more noticeable, making your winter air conditioning experience less than ideal.

How to Tell if Your AC System is Blowing Warm Air

A rising indoor temperature or feeling warm air coming directly from the vents are clear indicators that your AC unit might be malfunctioning.

What to Do to Troubleshoot

If you’ve gone through the troubleshooting steps and the problem persists, it’s time for a more in-depth examination. Check the outdoor unit for debris or obstructions and take a look at any electrical components for obvious damage.

When to Call a Professional

If you’ve attempted basic troubleshooting with no success, it’s time to consult a professional. Issues like refrigerant leaks, electrical problems, or complex mechanical failures require expert attention.

Cost to Fix AC Blowing Warm Air

While repair costs can vary depending on the required fix, homeowners can expect to pay from $100 for minor adjustments to $1,000 or more for more significant repairs. Being diligent about having your entire system checked on a regular basis can often prevent these issues, saving you money in the long run.

Who To Call

If you’re experiencing any problems with your HVAC system, you can trust the experts here at First Call Heating & Cooling. Since 1939, we have been a trusted name in HVAC services in Portland, OR, and the surrounding areas. With over 80 years of experience, we are a full-service residential heating and cooling company committed to customer satisfaction, quality, and integrity. Our technicians are licensed, bonded, and BBB-accredited. We offer expert HVAC services including same-day maintenance for all types of systems-gas, oil, or electric, and across all brands. From top-notch installations of new HAVAC equipment like furnaces and air conditioners to services that enhance indoor air quality, we’ve got you covered. We also provide reliable heating oil delivery. We’re committed to sustainable business practices and recycling, earning us a reputation for quality and trustworthiness. For all of your HVAC needs, call First Call Heating & Cooling at 503-231-3311.