How to Reset Wired Heat Detectors

Twist the cover off the heat detector with a counter-clockwise motion to remove it. Remove the internally-placed battery from the backup battery compartment. Spray the battery compartment's contacts with electrical cleaning spray. Insert new compatible batteries into the battery compartment and replace the cover. Press the "Test/Reset" (or similarly-named) button on a side of the detector. Release the button after the alarm sounds to reset the detector.

Trip the circuit breaker in the fuse box so that there's no electrical power going to the heat detector. Remove the screws surrounding the detector with a Phillips screwdriver. Pull the detector away from the wall or ceiling. Wrap strips of electrical tape around any exposed parts of wires that could be shorting out when touching another wire. Push the wiring back into the hole and return the detector to the wall or ceiling. Reattach the screws. Return the power at the fuse box. Press the detector's "Test/Reset" button on the side for a second and then release it.

Place a ladder against the wall where the heat detector is located, or beneath the ceiling where the heat detector is located. Hold an ice pack against the front grill of the heat detector to cool down the grill and force cold air against the sensor inside. Continue holding the ice pack against the grill until the sound or light ceases, indicating that the sensor has cooled down sufficiently to reset itself for proper operating. Remove the ice pack and put the ladder away.