Keeping cool with a fan when the ac is blowing cold air

Why is My Air Conditioner Blowing Warm Air?

It’s the first hot and muggy night in central Ohio and you turn on your air conditioner, only to find that there is no cold air emanating from the vents. “Why is my air conditioner blowing warm air” is the question that immediately enters your mind, while you wonder if you can find an HVAC service that performs emergency, middle-of-the-night service calls. If this happens to you, there are a couple of things to consider before trying to find an “all night HVAC emergency service” and pay for an expensive emergency AC service call.

What Is Your Thermostat Setting?

Believe it or not, we have been called on service calls for this exact issue and found that the HVAC thermostat is still set to heat! Left over from using your furnace during a cold Ohio winter… but since it hasn’t been cold, and probably hasn’t been run for awhile, the thermostat switch is still set to heat. Sometimes this is an oversight and sometime someone bumped the unit and changed the settings. Either way, make certain that the thermostat is set to cool your home and not heat it. Then make sure that the setting is to “auto” instead of “on” —  set incorrectly, your fan will keep blowing warm or room temperature air even when the AC unit is not cooling.

Blocked or Restricted Airflow Can Be the Issue

If your filters have not been changed recently, or if something is blocking the air ducts, the compressor on your outside unit might freeze up, as indicated by frost or ice on the lineset (the thicker line covered with insulation that runs to your outside unit). Then you will have warm or even hot air coming out of the ducts but with less force than normal. We see this when homeowners have neglected to replace the air filters often enough, or have not had an HVAC service performed for a long time. And, if you have neglected to get routine maintenance, the coils may be really dirty, adding even more airflow blockage.

Your Outside AC Unit Is Not Getting Electricity

The fan motor for your air conditioning system is actually inside the furnace of your home and gets its electricity from inside wiring. The outdoor cooling unit gets its power from a separate supply line. We often find that that problem when your AC unit is blowing warm or hot air is that the outside unit may need to have its wiring fixed. Or, it may just be that the circuit breaker or cutoff fuses for the outside unit have tripped and needs to be reset. If this is the case we must still check to make sure that there is not a short or some other issue that will just cause the breaker to trip again. Don’t just replace a fuse or reset the circuit breaker, call for professional HVAC help to make sure that there is not a more serious issue.

If You Have Not Had Your AC Unit Serviced in a While

Compressors that are not working are a common reason for the unit not producing cold air. You may have had a persistent noise that you ignored and now your compressor is broken. If you neglected to get your AC unit serviced before a hot and humid central Ohio summer, you need to do it now. You may possibly need a new compressor. But, if you are lucky, you may simply need  the refrigerant recharged. Low refrigerant causes the system to work harder, and leaves it unable to properly remove heat from inside the home.

About Dor-Mar Heating & Air Conditioning

In continuous operation since 1962, our expertise goes beyond just the mechanicals of your HVAC system. For top-notch service keeping your home’s heating and cooling system clean and your family breathing clean, filtered air, contact Dor-Mar today.

Our team offers a wide array of routine maintenance and emergency services for your heating and cooling system, allowing your family to breathe fresh, safe, clean air and be comfortable year-round. We also offer a number of add-ons to your HVAC equipment that can improve your home’s IAQ, such as electrostatic air filters, whole-house humidifiers, duct cleaning, Ultraviolet-C lighting systems, and more.

Schedule an appointment for HVAC system troubleshooting or maintenance with us today by using our online contact form, or call one of our seven neighborhood offices listed below. We pride ourselves on our customer-focused service, and our reviews show it.

NEWARK  740.345.6639 • COLUMBUS 614.238.6689 • DUBLIN 614.545.8939 • REYNOLDSBURG 614.365.1579 • WESTERVILLE 614.381.1540 • GROVE CITY 614.595.3098 • ZANESVILLE 740.454.2420

Dor-Mar…Your Climate Hero!

*Please note: neither the Centers for Disease Control(CDC), the World Health Organization (WHO), nor the manufacturer of our UV-C Devices have officially announced whether UV-C kills the current strain of Corona Virus (COVID-19). We urge you to err on the side of caution until we have a definitive answer, and take other measures to prevent the acquisition or spread of this virus.

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PLEASE NOTE: If you are a renter, please have your landlord/owner contact us directly to schedule service. We can only work with property owners.