Why Is My AC Not Turning On?

February 28, 2023

Once the warmer months are here, you expect your cooling system to be on when you need it. But for some reason, your air conditioner is not turning on. Whether you call an AC repair company depends on the issue, which you can narrow down by checking in a few places. Here are a few reasons for your AC not turning on and what you can do.

The Thermostat Isn’t Controlling the Unit

The first place to check when the AC won’t start is the thermostat. Perhaps it was turned off, in which case you can switch it back on. Or, it’s not set to signal the air conditioner to provide cooling. Reducing the desired temperature a few degrees should get the AC to kick in. 

However, if the thermostat’s display isn’t lit, change the batteries or remove the device’s front cover to check for debris or damage. If there’s any dust or dirt, remove it with a brush or compressed air. Then look for loose screws or wires to tighten and check the manual to verify the proper wiring configuration. 

If you find damaged wires or corrosion inside the thermostat, contact an AC professional for help.

The AC Isn’t Turned On

Every AC has an ON/OFF switch. It’s easy to overlook. Someone can also hit the switch accidentally or forget they turned the unit off. If there’s no other reason for your AC not turning on, flicking the switch on will get fresh, cool air blowing again.

The Air Filter Is Dirty or Clogged

The AC filter must be cleaned or replaced. If you forget to do this, the filter will eventually clog up, preventing air from circulating. Warm air from your home won’t reach the refrigerant, so it becomes colder until any moisture on the coils freezes. Changing the filter and letting the ice melt usually solves the problem; otherwise, you’ll need to consult with an AC professional.

The Circuit Breaker Has Tripped

The reason for your air conditioner not turning on may not be with the unit. If a circuit breaker tripped, the AC won’t have power. To reset it, make sure the AC is off, find the tripped breaker in the electrical panel, and switch it to the “On” position. Then wait at least 30 seconds before turning the air conditioner back on. It should start running; if not, call a repair technician. Also, call an electrician if the lights flicker when you turn on the AC or the breaker trips repeatedly.

The Drain Pan Is Full

Located below the inside unit, the drain pan catches water from the air conditioner. If it is full or clogged, a float switch will turn the system off to prevent damage. However, a water leak can still damage your walls, ceilings, and belongings. Blockages can be suctioned out with a wet/dry vacuum. If you’re not comfortable doing this or properly equipped, contact an HVAC technician.

There Is a Power Supply Issue

If the AC’s not turning on, the problem may be with the low-voltage wire, which provides electrical power to the unit. The system won’t start up if the wire is damaged or disconnected. A faulty high-voltage wire, which carries electricity from the outdoor unit to indoor components, can also be the cause. There may also be a faulty power cord, outlet, or circuit control board.

The Capacitor Has Failed

A start capacitor provides power to start the AC motor and disconnects when the motor reaches full speed. There’s also a run capacitor, which supplies energy to keep it running. A failed capacitor can prevent the AC from starting or cause it to start and stop abruptly. You might just hear clicking noises from the outdoor unit. The capacitor will need to be replaced by a professional.

The Motor Is Damaged

When you try to turn on the AC and hear a grinding noise, the unit’s motor is damaged. A broken seal causes it to lose oil, and a lack of lubrication will wear it out. If the motor stops working, the outside unit cannot dissipate heat (a faulty indoor blower motor can prevent the AC from running as well). An HVAC specialist will inspect the system to determine whether to replace just the motor or the entire unit.

The AC Isn’t the Right Size

An air conditioner that is the wrong size for your home will work harder and eventually break down. The reasons are as follows. Too large a unit will constantly turn on and off, and wear and tear will quickly take a toll. Too small a unit will run much longer, which can cause the capacitor to overheat. Replacing the unit is the only solution to this problem.

Contact Service Champions If Your AC Is Not Turning On

Our certified HVAC service technicians are here to help when your air conditioner stops working. We’re open 7 days a week and equipped to diagnose and repair any problem. Prompt repairs will restore your comfort and safety while our team will do what it takes to prevent future issues. If you find your air conditioner not turning on, contact us online or call 833-600-0991 for professional AC repair.

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