Why Is My Air Conditioner Not Cooling My House?

air conditioner not cooling

Did you know that 88 percent of homes in the United States have some sort of air conditioning? Even if your home is in that 88 percent, you may not feel like it if your air conditioner is underperforming. You may have noticed that your air conditioner just isn’t keeping up this year, and you might be suffering the consequences. 

There are a few things that can cause your air conditioner to struggle during the summer months this year. Read on to answer the question, “Why is my air conditioner not cooling?” and discover what you can do about it.

Wrong Thermostat Settings

If your air conditioner is not cooling enough, one of the first things you should do is to check the thermostat settings. Sometimes, getting your A/C back up and running can be as simple as switching the mode your unit is running on. A power outage could have shut off your thermostat, or it could have gotten switched into heat mode.

Check to make sure your thermostat is up and running and set to the “cooling” mode. If it is, make sure the temperature is set to an appropriate range and that you don’t have it set to “fan only” mode. If everything seems to be working properly, try turning your system off and then back on again before calling a technician.

Dirty Air Filter 

Aside from improper air conditioner settings, a dirty air filter is one of the most common causes of air conditioner filters. Your air conditioner filter catches dust, dirt, pet hair, and allergens that make their way into your air conditioner. Over time, these substances can clog your filter, making it hard to get any air through it. 

The dirtier your filter gets, the harder your air conditioner has to work to keep your home cool. If this goes unattended long enough, it can even burn out your air conditioner motor. If your air conditioner doesn’t seem to be cooling as efficiently as it used to, start by cleaning or replacing your air conditioner filter.

Blocked Outdoor Unit

There are two primary types of outdoor air conditioner units: a condenser and a heat pump. Both units have a series of coils or fins that compressed refrigerant flows through. As the refrigerant moves through the coils, it cools down until, by the time it leaves the condenser, it’s cool and can be used to cool down the air that flows into your home.

Over time, those coils can gather dust, dirt, and other debris, blocking air access to the coil. This means it can’t cool the refrigerant as effectively, so your home doesn’t get as cool. If the air coming out of your vents seems to be tepid at best, you may want to have your condenser unit or heat pump checked and, if needed, cleaned.

Frozen Evaporator Coil

In addition to your condenser or heat pump, your air conditioner has an indoor unit called an evaporator. Once the refrigerant in your system has been cooled, it gets pumped back inside and through another series of coils. The cooled refrigerant absorbs heat from the air around the coil, and either pumps that heat back outdoors or passes the chilled air into your ducts, depending on your system.

Unfortunately, if your air filter gets too clogged, your system may not be able to pull enough air into your evaporator coil. The refrigerant may not have enough heat to absorb from the air and so may get cooled down too much, freezing up the unit. A frozen evaporator coil will stop your whole system dead and is a common culprit when air conditioners aren’t cooling.

Refrigerant Leak 

You may have noticed that refrigerant plays a critical role in shifting heat around in your house. In most systems, this refrigerant has to be compressed so it can move through the system and transfer heat efficiently. Unfortunately, this pressurized system means that sometimes your refrigerant lines may spring a leak. 

If your refrigerant starts leaking out, your air conditioner won’t be able to absorb as much heat. This can also be why your air conditioner is not blowing cold air. If you notice your house is warmer than usual, it’s a good idea to have your refrigerant levels checked so you can locate the leak and fix it.

Undersized Unit

In rare cases, even if your air conditioner is in perfect working order, it may still be unable to keep your home cool. Air conditioners come in different sizes that are appropriate for different sized homes. A unit that’s too small won’t be up to the task of keeping a house cool, even when it’s working at its best. 

If the person who installed your air conditioner wasn’t up to snuff, they may have installed a unit that was too small. If any major additions have been put on your house, that can also overtax your air conditioner. Unfortunately, if this is the problem, the only solution is to install a unit that’s big enough to fit your needs. 

Answer, “Why Is My Air Conditioner Not Cooling?”

Living with an air conditioner that’s not cooling can be miserable during the hotter months of the year. There are a few reasons your air conditioner may not be cooling, ranging from a dirty filter or coil to leaking refrigerant or an undersized unit. Start by checking your thermostat settings and then call in a pro to find the source of the problem.

If you’d like to answer the question, “Why is my air conditioner not cooling?” check out the rest of our site at All Comfort Heating and Cooling. We offer expert heating and A/C repair, new HVAC system installation, and HVAC preventative maintenance. Contact us today and get an air conditioning company who will do what’s best for you.

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