One should not attempt to troubleshoot an air conditioner if the act of troubleshooting poses a safety risk. Since an air conditioner is an electrical appliance, there are certain situations where electrical surges can pose a serious risk.
If the thermostat sensor of an air conditioner is broken, it requires a licensed technician to fix it. The air conditioner should be turned off in this case to ensure safety.
If an air conditioner is leaking refrigerant, this can become dangerous as it leaks chemicals into the atmosphere. As such, refrigerant leakage also requires a licensed technician.
If an air conditioner makes a loud banging noise, this is most likely because of a dislodged fan belt. It is very important to turn the device off in this case and call a licensed technician to fix it.