How to Shut an Air Conditioner Off During a Fire Alarm

Raise the thermostat dial or raise the thermostat sliding switch -- depending on the make -- fully clockwise or as high as it will go. This will inform the air conditioner that the desired ambient temperature of the home has been reached, causing the motor to shut off.

Go to the fuse box -- typically located in the basement or a utility room or a broom closet. Pull the appropriate fuse or trip the appropriate circuit breaker -- depending on the make of the fuse box -- to discontinue power to the air conditioner, which will immediately shut down.

Locate the Heat/Cool switch that is beneath the dial or to the left or right of the slider switch on the thermostat. Slide the switch from "Cold" to "Heat" -- the actual name may vary depending on the model. The motor of the air conditioner will now shut down since the system's been told that cold air is no longer desired.