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My A/C Is Running but Not Blowing Cold Air

Summer is in full swing and, on really hot days, all you want to do when you get home from a long day is to enjoy some cool air conditioning. Nothing kills this excitement more in the warm summer months than entering your home only to realize that your A/C is not blowing cold air. Unfortunately, an A/C is not fail-proof and they can quit blowing cool air for a variety of reasons. We have listed some of these reasons below so you can have an idea of why your A/C quit working and how you can resolve the issue.

Reasons Why Your A/C is Running but Not Blowing Cold Air

1. Your Thermostat Is Set Incorrectly

Sometimes an A/C doesn’t blow cold air simply because your thermostat settings need to be adjusted. Luckily, this is a pretty easy issue to resolve on your own. Some people think that leaving their A/C running all day is the best way to keep their home cool, but it is actually best to set your fan to AUTO, this will ensure that your air conditioner is running only when it is actually cooling the air. Changing this setting will help save money on energy bills, ensure that you don’t wear out your A/C too quickly, and keep your home cool.

2. Your Air Filter Is Dirty

Having a dirty air filter can inhibit airflow which could definitely be a reason that your A/C isn’t blowing cool air. Take out your air filter and see if there is any debris. If you do notice that the air filter is dirty, swap it out for a new one and get in the habit of changing it out every month.

A great way to ensure that your air filter is clean and your A/C works all summer long, we suggest having professional regularly scheduled maintenance.

3. Your Outside Unit Is Dirty

In the same vein as point number two, having an outside unit that is covered in dirt, dust, and other debris could also be inhibiting cool air from making its way into your home.

Air conditioners work when the inside unit (called an evaporator) absorbs heat from the air and then transfers that heat to the outside unit (called the condenser). The condenser can’t properly dissipate heat if it’s dirty or crowded with debris.

You can resolve this issue by spraying the outside unit with a garden hose on a gentle setting and removing weeds and overgrowth around the unit.

4. Refrigerant Leak

Refrigerant is the liquid that absorbs the heat from the air. When you don’t have enough refrigerant, your A/C can’t absorb enough heat to cool the air. Refrigerant leaks are fairly common and can definitely be the reason why your A/C isn’t blowing cold air.

Signs you have a refrigerant leak include:

  1. Ice buildup on the outside unit and line
  2. Bubbling or hissing noises
  3. Your A/C doesn’t cool the home on hot days but works fine on cool days and at night

If you see these signs, turn off your A/C immediately and call a professional. Refrigerant chemicals are very dangerous and need to be handled by the experts.

5. Air Duct Leaks

Over time, the air ducts that move air conditioning through your home may become loose or their seal may be compromised. This means that air is escaping erratically which makes it hard to keep your home at the temperature you want. You will need to have a professional come out and evaluate your air ducts to ensure that they are not leaking cool air and make repairs as needed.

6. A Bad Compressor

The compressor is one of the most important parts of the A/C system and pushes the refrigerant through the unit. If your compressor isn’t working properly, your A/C cannot work. Compressors need to be evaluated by a professional and replaced if they appear worn out or defective. Unfortunately, compressors are expensive unless you have a warranty. Chances are if your compressor is bad, you’ll probably need to replace an entire outside unit.

7. Dirty Evaporator Coils

An evaporator coil is the part of the A/C system where the refrigerant absorbs heat. Over time, the evaporator coils get dirty and affect the performance of your A/C and make it harder to remove warm air.

Dirty evaporator coils can lead to your A/C overheating and potentially shutting off completely. Evaporator coils should be evaluated and cleaned by a professional to ensure that they are in good condition.

Schedule an Appointment and Stay Cool All Summer Long

If your A/C is not blowing cold air, contact our licensed Chicago HVAC technicians. They can help troubleshoot the problem so you can cool down and relax again. Contact us at 815-455-7000 to schedule.

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