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Central AC 101 For Homeowners: Troubleshooting Tips

It is officially summer! And that means it’s do-or-die time for your central air conditioning system.  If you’ve just cranked yours up and feel that it’s not running at peak performance, there could be several reasons why.

Low Refrigerant:  If your central air conditioning system  is low on refrigerant, either it was undercharged at installation or it leaks. A trained technician should fix any leak, test the repair, and then charge the system with the correct amount of refrigerant. Remember that the performance and efficiency of your air conditioning system is greatest when the refrigerant charge exactly matches the manufacturer’s specification, and is neither undercharged nor overcharged.

Sensor Problems:  Your air conditioning system’s thermostat sensor, located behind the control panel, measures the temperature of air coming into the evaporative coil. If the sensor is knocked out of position, your air conditioning system could cycle constantly or behave erratically. The sensor should be near the coil but not touching it; adjust its position by carefully bending the wire that holds it in place.

Thermostat Issues:  Check your thermostat to make sure it is set properly and it is reading the correct temperature.  Also make sure your thermostat is working – it might need new batteries or even need to be replaced entirely.

Dirty Filter:  A clogged filter restricts airflow through the unit, decreasing its efficiency and reducing its ability to effectively cool the air.

Electric Control Failure:  Your compressor and fan controls could be worn out from having your system turned off and on too quickly.  Contact a professional to check your system’s electrical connections.

Check Fuses and Circuit Breakers:  If your air conditioning system fails, begin by checking any fuses or circuit breakers. Wait for about five minutes before resetting any breakers. If a central air conditioning system’s compressor stops on a hot day, the high-pressure limit switch may have tripped. Reset it by pushing the button, located in the compressor’s access panel.

The above are just a few reasons why your unit may not be cooling.  If you’ve checked the above and the unit still isn’t cooling, call your local cooling company to have someone check out the system. But the best way to avoid some of these issues is to make sure to schedule an AC tune-up at the beginning of every season. 

Source: energy.gov