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Why Is My AC Not Cooling Air?

woman trying to cool down with fan on couch

If you're feeling hot and sticky, and your air conditioner is not providing the relief you need, it's time to troubleshoot. There are several common reasons why a central AC system might not be cooling air as it should. In this blog post, we will explore some of the most likely causes of this problem and offer solutions. Read on to learn more!

Incorrect Thermostat Settings

Your thermostat is like your air conditioner’s command center, giving orders to the system. If something is wrong with the thermostat, or if it’s not set correctly, you won’t get cool air.

Is your air conditioner:

  • Blowing out warm air? Make sure the thermostat is set to “cool” and “auto,” not just “on.” The “on” setting tells the fan to run, even if the refrigerant isn’t absorbing heat out of the warm air in your home (or in other words, cooling it).
  • Not turning on? Make sure your thermostat is receiving power and set to a low enough temperature to make the system turn on.

Blocked or Partially Closed Air Vents

Does it feel like your AC is struggling to cool your home? Make sure to double-check that every air vent in your home is: 1) not blocked by any furniture or decor, and 2) completely open. This is especially important if you’ve just moved into a new home, where you may be unfamiliar with the air vents and how the previous homeowner left them.

A Dust-Clogged HVAC Filter

Your system’s filter helps trap dust and keep it out of your HVAC equipment and air ducts. After a while, dust can blanket the filter to the point where air has trouble passing through. That lack of airflow will make it difficult for your AC system to circulate cool air effectively through your home. At worst, the system may break down altogether from strain and overheating.

You should change your system’s filter at least once every 90 days. During summer, if you’re relying on your AC daily, we recommend changing the filter as often as every 30 days just to be safe, especially if you own pets or have a particularly dusty home.

A Grimy, Dusty Evaporator Coil

One potential reason why your air conditioner is not cooling properly is that the evaporator coil may be dirty. The evaporator coil is located in your home's indoor AC unit. It's primarily responsible for absorbing heat from the air in your home. If this coil is covered in dirt and dust, it will not be able to function properly and your AC unit will not be able to cool the air in your home.

Getting your AC's evaporator coil cleaned is a part of routine HVAC maintenance. We recommend scheduling this maintenance for your air conditioner once a year in the springtime. If you can't remember the last time a professional cleaned and tuned-up your AC, it's time to schedule a maintenance appointment!

No Power

If your air conditioner isn't cooling air at all, either your thermostat, the indoor unit, or the outdoor unit may not be getting power. This is likely because a circuit breaker has been tripped. Visit your home's circuit breaker panel to see if you need to reset any of the breakers.

If a circuit breaker isn’t the issue, check to see if the power switches are on indoors and outdoors. Your indoor unit’s power switch will be located either on the unit or on the wall next to it. Your outdoor unit’s power switch will be located next to it, usually on the side of your home.

Air Conditioning Service in Milford, CT

There’s no need to suffer through summer! At Tri-City Heating and Cooling, our friendly HVAC technicians provide top-quality air conditioning maintenance, repairs, and installations in New Haven and Fairfield Counties. Schedule your service by calling us today at (203) 303-5700.