Troubleshooting Guide: Why Is My AC Not Running? Common Causes and Solutions

Check the Thermostat

When your AC stops running, the first thing to assess is the thermostat. Make sure it is set to "cool" and the temperature is set lower than the current room temperature. Double-check if it's on "auto" or "on," as these settings can affect the operation of your AC.

If the thermostat is battery-operated, try replacing the batteries. Sometimes, a simple battery change can resolve the issue. If everything seems fine but your AC still doesn't start, consider resetting the thermostat to see if that helps.

Inspect the Circuit Breaker

A common reason for an AC not running is a tripped circuit breaker. Go to your electrical panel and locate the breaker assigned to your AC unit. If it's in the "off" position or somewhere in between, switch it off completely and then back on. This action can reset the breaker and potentially solve the problem.

If the breaker trips again soon after resetting, there might be a deeper electrical issue. In such cases, it's best to consult a professional electrician to avoid any hazards.

Examine the Air Filter

An often overlooked cause of AC malfunction is a clogged air filter. When air filters become dirty, they restrict airflow, causing your AC to work harder and sometimes stop altogether. Check your air filter and replace it if it appears dirty or clogged.

It's advisable to change air filters every one to three months, depending on usage and environmental factors. Keeping your filters clean not only ensures efficient operation but also improves indoor air quality.

Look at the Condenser Unit

Your AC's condenser unit, located outside, can be another source of trouble. Ensure that it's not obstructed by debris such as leaves, dirt, or grass. Clear any blockages to allow proper airflow. If the unit seems excessively dirty, consider hosing it down or having it professionally cleaned.

Ensure the surrounding area around the condenser is clear by at least two feet to ensure optimal performance. Regular maintenance of the condenser unit can prevent future issues.

Investigate Refrigerant Levels

Low refrigerant levels can prevent your AC from operating effectively. Signs of low refrigerant include ice buildup on the unit or warm air coming from the vents. Unfortunately, checking refrigerant levels isn't a DIY task and requires a professional HVAC technician.

If you suspect a refrigerant issue, contact an expert who can properly diagnose and recharge your system if necessary. Regular maintenance checks can help catch this issue early.

Conclusion

While some AC issues can be resolved with basic troubleshooting steps, others may require professional assistance. Regular maintenance and timely checks can prevent most problems before they turn into costly repairs.

If you’ve gone through these steps and your AC still isn’t running, it may be time to call a professional HVAC technician to diagnose and fix the problem. It’s always better to address potential issues early rather than wait for a complete breakdown.