Why is my air conditioner not blowing cold air?

You know the old joke: if your air conditioner is running, you had better go catch it.

If your air conditioner is running but not blowing any cold air, you have to take an entirely different approach.

Let’s review some of the common causes behind this distressing issue. While there are a few simpler causes behind this issue, it is often complex and requires some troubleshooting that a trained HVAC technician is best equipped to help you with.

1. Lack of adequate air flow.

In a properly working air conditioner, a fan draws air over evaporator coils to cool it. That air is then recirculated back into the home.

If your air filter is dirty or clogged, the air flow over the evaporator coils can be impacted. This in turn can cause the coils to become too cold. Frost or ice can form on them, restricting the airflow even more. This will result in little or no cool air being circulated in the room.

Preventative maintenance on your air conditioning, including regular replacements of your air filter, can help to reduce the risk of this happening.

2. Problems with your thermostat.

Your thermostat monitors the incoming air temperature and turns the compressor on or off. If your thermostat or the temperature control is defective or experiencing issues, it may not send power to the compressor.

At a basic level, ensuring your thermostat has power is a good troubleshooting check. If this does not appear to be the issue, there may be problems with the sensing bulb or another issue at play. A trained HVAC technician can help you to diagnose the problem.

3. Your fan or fan motor is broken.

If your circulating fan is not running or running too slow, little or no air flow will be drawn back into your home. If the motor is seized or if the fan blades are damaged, they may need replacement.

You can start with a simple check of your outdoor A/C unit. Clean around the area for any debris and weeds that may be blocking air circulation. The expertise and support of a trained HVAC professional can assist with a diagnosis and any necessary parts replacements for this issue.

4. Other potential causes that require an HVAC professional.

A broken fan or fan motor is certainly one big reason to pick up the phone and call for professional help with your air conditioner! Here are a few other potential reasons which you may experience:

  • Low refrigerant level. If you have ice buildup on the refrigerant line or outside unit, or you hear a bubbling/hissing sound, you may have a leak. It is important to turn off your air conditioner right away and call a professional to avoid damage to your compressor.
  • Problems with your compressor. The compressor is at the heart of your air conditioning system, moving the refrigerant around as needed. A professional technician can tell you if this compressor requires replacing.
  • Thermistor problems. The thermistor is a component found on electronic control models. It monitors the incoming air temperature and is responsible for signaling the main control board to turn the compressor on or off. Your HVAC technician can tell if you if it is showing any signs of damage or corrosion!

There are many different factors at play when it comes to an air conditioner which is running but not blowing cold air. For your home comfort and the long-term functionality of your air conditioner, a trained HVAC technician is best able to support you with this issue.

Call us today at 1-800-487-7307 for all your A/C questions! We also offer 24/7 emergency service.

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