A lack of maintenance – if the filters aren’t cleaned or the coils aren’t kept clean, it can cause the AC to break down. 2. Incorrect installation – if the AC isn’t installed properly, it can lead to breakdowns. 3.Age of the AC – over time, all machines will wear down and eventually need to be replaced. 4.Extreme weather – if the AC is used in an environment with extreme temperatures (either very hot or very cold), it can cause the machine to break down. 5.Power surges – if there is a power surge, it can damage the AC and cause it to break down. 6.Compressor issues – if the compressor isn’t working properly, it can cause the AC to break down. 7.Refrigerant leaks – if there is a refrigerant leak, it can cause the AC to break down. 8.Dirty ductwork – if the ductwork is dirty, it can restrict air flow and cause the AC to break down. 9.Thermostat issues – if the thermostat isn’t working properly, it can cause the AC to break down. 10.Damaged parts – if any of the parts of the AC are damaged, it can cause the machine to break down.