Why is my air conditioner not cooling?


An air conditioning unit not cooling is is a very concerning situation in a desert climate. In areas where heat reaches triple digits, there is no worse feeling than waking up or coming home to a hot house. Ever wonder what are some of the most common reasons for an air conditioner that isn’t cooling? This short article walks you through some of the causes that are easy fixes and other more complicated problems that can lead to your air conditioner to stop cooling your home.

Possible Reasons why your A/C may not be cooling:

Let’s start with two of the most obvious problems we see with air conditioning units.

Filter Change

Filters, which should be changed monthly, can prevent the unit from cooling efficiently. A dirty air filter will block air circulation, and eventually, cause your unit to malfunction.

Age of Unit

Generally, an air conditioner wears out around that time depending on the brand. Older units tend to need more up keep and maintenance and when they stop cooling it can be any one of a number of things wrong with older units.


If your unit is not cooling, it may be due to the settings on your thermostat. Always check to make sure your settings are correct and the thermostat is set to on and that settings were not changed by accident.

Blocked Condenser

In the same way a dirty filter can block airflow, dirt in the condenser unit can cause the unit to stop cooling. Sometimes weeds, trees, or bushes can get stuck in the outside unit, which will cause it to eventually shut down.

Frozen Unit

There are several issues that could be causing this, from low refrigerant to a fan malfunction. If you notice ice on the condenser, turn off the unit. Continuing to run the unit risks compressor damage.

Refrigerant Leak

Leaking refrigerant is common in older units if you suspect a leak, be sure to call a professional right away to help reduce environmental harm.

Inadequate Maintenance

Here’s a question to consider: What would happen to your car if you failed to ever change the oil? The delicate machinery we use to heat and cool our homes requires routine maintenance, just like your car. Failing to keep up with maintenance is the number one reason for equipment failure. The best way to make sure your system cools all summer long is to have a Spring and Fall tune-up to watch for issues that could turn in to big problems.

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