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During a hot, humid St. Louis summer, the air conditioner is the most important appliance in your house. The compressor is a key component of the AC, so if something goes wrong, it’s important to find a solution quickly. Whether the AC compressor isn’t turning on or the system is running inefficiently, a quick repair can help you maintain a comfortable temperature and avoid a system failure.
What Is an AC Compressor?
The compressor is an important part of your AC system. It pressurizes the refrigerant in your AC and pushes it into the system so it can circulate through the unit. That’s critical because the refrigerant transfers heat from inside your house to the outdoors.
When the compressor isn’t working properly, it affects the entire AC system. Some compressor problems are easy to resolve, while others require professional help.
Bad AC Compressor Symptoms
Because the compressor is such an important part of the AC system, it’s usually relatively easy to spot problems. If you suspect your AC might need a repair, keep an eye out for these warning signs.
Your AC Is Blowing Warm Air
The compressor drives the cooling system, and when it’s having problems, the AC might not work properly. You might notice that the vents blow only warm or moderately cool air, even when you turn the thermostat to the lowest setting.
The AC Compressor Is Not Turning On
If you’re experiencing AC issues, turn down the thermostat and make sure it’s set to the cooling function. Then, go out to the compressor unit. If you don’t hear a loud hum, it probably means the AC compressor isn’t turning on.
The Compressor Makes Unusual Noises
When you’re near the outdoor compressor unit, does it sound different? Strange noises or vibrations can indicate a mechanical issue within the compressor.
The Breaker Trips When the AC Starts
When your AC trips the circuit breaker every time it kicks in, it could mean there’s an electrical problem with the compressor. This could happen if the motor is shorting out or another internal issue causes the compressor to pull more energy than usual.
Your AC Stops and Starts Frequently
When you’re at home during the day, do you notice the AC turning on and off more often than usual? This is called short cycling, and it usually happens when the system struggles to maintain your set temperature. It isn’t usually caused by a bad compressor, but it’s a cause for concern if you’re experiencing other symptoms. Short cycling puts a lot of strain on the compressor, which could cause it to fail if it’s already experiencing other issues.
Troubleshooting AC Compressor Problems
If you’re seeing any bad AC compressor symptoms, there are a few DIY fixes you can try.
Reset the AC Compressor
When your AC compressor isn’t turning on, it doesn’t always mean there’s a serious issue. Sometimes, the system simply needs to be reset.
Follow these steps to reset an AC compressor:
- Switch off the circuit breaker for the AC.
- Turn off the cooling function at the thermostat.
- Press the reset button on the compressor unit for 5 seconds and release (check the manual for button location and hold time).
- Switch on the circuit breaker and turn your thermostat back to the cool setting.
- Make sure the compressor is running normally and the AC is cooling your home.
Keep in mind that not all AC compressors have a reset button. If you can’t find one, you can turn off the circuit breaker, wait a few minutes and turn it back on.
Change the Air Filter
Dirty air filters block airflow into your AC, which can cause it to run inefficiently. Fortunately, this is an easy fix for a wide range of AC problems, including an AC that freezes up. Replace the filter with a clean one, and see if it resolves the problem. While you’re at it, make sure nothing is blocking the vents inside your house; this can also restrict airflow.
Clean the Compressor Unit
When debris builds up around your outdoor compressor unit, it can cause problems. Clear away leaves, dirt, and brush. It’s also a good idea to cut the grass around the compressor. Ideally, there should be at least 2 or 3 feet of clearance to allow air to move in and out.
If you feel comfortable with basic maintenance, you can also cut the power to the condenser and clean the housing. Vacuum away any debris, and make sure the vent openings are clear. A professional can handle this for you if you schedule an AC maintenance appointment.
Check the Outdoor AC Disconnect
The AC disconnect is a safety feature that cuts the power to your compressor during an emergency or a repair. It’s usually located on the exterior of your home near the compressor. Inspect it for signs of damage, and make sure the switch or the pull-out block handle is turned to the “on” position.
When to Call a Professional to Fix an AC Compressor?
It’s not always feasible to fix an AC compressor issue on your own. If you’ve tried DIY solutions and you’re still experiencing problems with the AC, it might be time to call a technician. Your compressor might be failing, or there may be an issue with the refrigerant or the thermostat wiring that requires professional tools and expertise to diagnose and repair.
When your air conditioner compressor isn’t turning on, summer in St. Louis can get very uncomfortable. Call us today and we’ll schedule an inspection and recommend a repair.
