If your air conditioning unit has stopped working, many possible reasons can explain why. It could be your thermostat, your air filter, a problem with the condenser or compressor, or it may just be time to replace the unit, especially if it's over 10 years old.
Simple Causes for an AC Unit Suddenly Stopping
Here are a few common causes: Circuit Breaker: Your AC unit may stop working if the circuit breaker has tripped. Resetting the circuit breaker might solve the problem. Thermostat Settings: A wrongly set or faulty thermostat can also cause your AC to stop working.
AC Problems that Cause Your Unit to Shut Off
Unit is overheating – This usually indicates that there is grime buildup within the compressor, but it could also be indicative of a more complex refrigerant leak. Faulty thermostat – The wiring may have been damaged on your thermostat, or there may be an electrical problem.
Make sure it has power (check outlet if a window unit, check circuit breaker if hardwired). Check thermostat battery if accessible (some wall units use a battery). Check if filters are clogged. Check outside duct for obstructions.
If you have fuses, you can only reset the AC by taking the fuse out. After the 30 minutes lapses, reinstall the fuse back in position if it's still in good condition, but replace a worn-out fuse with a new one. Now turn the AC back on, confirm if the thermostat is set to cool, and observe how the unit functions.
In AC systems, the air conditioner reset button is on the outside unit's lower edge, typically close to the ground. Some models have the reset button located behind the service panel, which may require tools to remove. Reset buttons are usually red or yellow with a clear “reset” label.
Yes, you should turn off your AC if it's not cooling.
An AC compressor can overheat, malfunction, or begin failing, all of which can trigger your air conditioner turning on and off. A compressor failure would need to be diagnosed by a professional HVAC technician.
The most common reasons for a blank thermostat screen are dead batteries, a power outage, a tripped circuit breaker, faulty wiring, or a failed thermostat.
Change the air filters: Dirty air filters can cause the AC unit to overheat and turn off by itself. Changing the air filters regularly can help prevent this issue. Check the thermostat: Make sure the thermostat is calibrated correctly and set up properly for your home's climate conditions.
Power issues: A tripped circuit breaker or blown fuse in your home's electrical system will prevent your AC from starting. Thermostat problems: Make sure you have your thermostat set to “cool” and the temperature is set below the current temperature in the room.
Checking basic thermostat settings, power supply components, and air filter conditions are essential to troubleshoot why an AC unit isn't turning on. More advanced issues requiring professional attention include faulty wiring, a malfunctioning outdoor unit, a bad capacitor, or incorrect thermostat calibration.
There are a number of reasons why your air conditioner might be running but not cooling. It could be an issue with the thermostat, the compressor, or the evaporator coils. Or, it could simply be clogged with dust and debris, which is preventing it from working properly.
When the AC compressor overheats, it short cycles and turns off. A dirty air filter, dirty condenser coils, and low refrigerant all cause your compressor to overwork and short cycle. Short cycling is particularly common at the beginning of the season.
When you head out of town for a few days, a week, or even more, it's much safer to leave the cooling system running than to turn it off. This is because summer conditions can cause damage inside your home if there is no AC unit running to help keep them under control.
Your air conditioner's internal circuitry needs some time to reset after you turn it back on. This can take approximately a half-hour, so sit tight for about 30 minutes. How to reset air conditioner after power outage at the thermostat. After 30 minutes have passed, turn your air conditioner back on at the thermostat.
First, check your filters and coils for dirt and debris that may be impeding airflow. Once you've cleaned the filters and coils, run the air conditioner with just the fan so that the ice accumulation can melt off. If the AC still doesn't blow cold air, it could be that refrigerant levels are too low.
The average cost of an HVAC service call is about $100 to $250, depending on the problem. The total hourly rate for an HVAC technician ranges from $65 to $150+ per hour, with additional parts costing anywhere from $40 to over $1000.
Wear and Tear on the Fuse
The lifespan of a fuse can be up to 20 years. AC fuses are usually what is known as 'slo-blow' or 'time delay' fuses. This means that they are at work every time you turn the machine on and off and eventually, will simply wear out due to the strain of the operation.
Residential Air Conditioner Freon Refill Cost
As mentioned earlier, Freon costs about $125 – $150 per pound. Most homeowners will pay in the range of $200 to $400 for a refill, depending on the type and size of their HVAC unit. If you own a larger r22 unit, you may have to spend $600 or more.