7 Reasons Why Your Central AC is Not Blowing Cold Air

If it’s hot outside and you come home to find that your central AC is unable to cool down your house, it can be frustrating.

Is your central AC not blowing cold air? If so, there are several reasons why this might be happening.

The underlying problem might be something you can handle yourself. However, in other instances, calling a professional technician is the ideal solution.

One thing you should always note is that when an AC malfunctions, immediate action is necessary to remedy the problem. This way, you can prevent further damage to the system, and most importantly, get the cool environment that you desire.

So, why is my central AC not blowing cold air? If that’s your question, here are some of the most common causes.

My Central AC is Not Blowing Cold Air: Common Reasons

1. Dirty filter

Filters are most often found around the indoor air handler system. They are prone to catching dust, airborne particles, and dirt as the outdoor air makes its way into the air handler unit. Their primary task is ensuring that the air that gets into your home is clean. A dirty filter is a pending disaster. It blocks the airflow hence reducing the amount of cool air that enters your home. In the worst-case scenario, it completely shuts down the entire AC unit. To resolve this, ensure that you often clean or replace your filter. Your filter should be changed approximately every three months. Fortunately, you can replace the indoor air filters yourself without calling an expert. But, if you are not well-versed on how to go about it, reach out to an HVAC professional and get the air filter changed.

2. Incorrect Setting of the Thermostat

Another reason why your central AC is not blowing cold air might be the setting on the thermostat. The thermostat is the main component controlling your AC unit’s functions. Until the air temperature in a room is above the control setting, the AC cannot turn on. So, the first sure thing to do is to ensure that you have not altered the thermostat setting. Sometimes, the thermostat setting might be higher than the room temperature, or reading “heating” instead of “cooling.” In such scenarios, the AC system will not blow cold air into your home. Simply changing the settings to cool or auto modes will solve such a problem. If your thermostat is set correctly and the AC is still not turning on, then the problem might be with the thermostat itself. If you replace the batteries and the issue persists, calling a professional should be the next step taken to resolve the issue.

3. Clogged or Blocked Vent

Just like a clogged air filter, air restrictions in the system’s vents or registers will cause problems. And, this might cause your central AC not to blow cold air. For this reason, check all of your vents to make sure there are no obstructions blocking the proper circulation of cool air throughout your home. Remove any dust, debris, and other obstructions from each vent using a vacuum cleaner.

4. Power Issues

This might sound obvious, but if your AC is not blowing cold air, the problem could be a power connection. You should ensure that the power cord is connected correctly before blaming your AC unit. Also, ensure that the AC is plugged into the right outlet. If both of them are okay, the problem could be with the electrical panel.

5. Low Refrigerant

The problem of a central AC not blowing cold air can also be caused by low refrigerant levels. In this case, you should first check for any refrigerant leaks. More often than not, leaks cause refrigerant levels to plunge. You can also have this problem checked by a professional to determine if it’s the cause of your AC unit’s malfunctioning. If it is, they will likely add more refrigerant to the system to get it up to par.

6. Frozen Evaporator Coil

An evaporator coil is a vital component in an AC system. If the evaporator coil is frozen, the warm air won’t be cooled down before circulation. This means that the central AC will not blow cold air.

The following are the indicators of a frozen evaporator coil:

  1. Insufficient cooling
  2. Escalating utility bills
  3. Frost forming on the outdoor unit or exterior refrigerant tubing
  4. Unrestricted condensate drainage around the indoor unit

Note that gaining access to the evaporator coil can be challenging. Therefore, to resolve the frozen evaporator coils problem, hire the services of an HVAC professional.

7. Obstruction of the Condenser Coil

Finally, another reason as to why the central AC is not blowing cold air could be a clogged or jammed condenser coil. Airborne particles, grass, and dirt are some of the main causes of a clogged coil.

A dirty coil usually causes loss of air at the vents, complete AC shutdown, damaged compressor, or low energy efficiency. You can do the following to clean the coil:

  1. Use a brush attachment to vacuum the coil
  2. Rinse the coil using a hose

If you correct the above-mentioned issues, you will not be dealing with unbearable heat in your home during the hot summer months. The best news is that all these issues are resolvable so, there is no cause for alarm.

If your central AC unit is not blowing cold air, all you need is to troubleshoot each of these issues until you find the root cause. And if you still can’t seem to fix the problem, contact a professional for assistance.

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