To replace a smoked detector hardwired with a backup battery you need to turn off the household power to the circuit supplying by switching off the circuit breaker. Access smoke detector by using a ladder or a chair and remove the smoke detector from the mounting base. You have to turn the smoke detector counter-clockwise but in case if smoke detector doesn’t disengage then it might be due to tamper-resistant mounting bracket.

Release by shifting the locking pin into the unit. You don’t need to push it immediately and tilt the smoke detector to the side by locating the wire connector leading into the unit. Unplug the wire from the smoke detector or mounting base. Return the smoke detectors battery at the door normally located either on the side or the back of the unit. Now you need to Reconnect the wiring harness to the unit or base, apply the unit into the base and turn the unit clockwise engage it on the base Francis Fire Protection Services Ltd.
Turn on the circuit breaker for restoring household power to the detector’s circuit. Finally, examine the smoke detector with the test button. When it comes to replacing the Smoke Detector Batteries you have to access the smoke detector within a chair and to replace the battery you should twist the detector counterclockwise. Release the detector with the mounting plate remaining on the ceiling. Most of the smoke detectors possess a tamper-resistant feature for preventing children from removing the device.
Disengage it with a locking pin and replace the battery by following the smoke detector instructions. Set the smoke detector back in the mounting bracket and lightly turn clockwise. The smoke detector should engage. Examine the smoke detector with the testing button that is placed on the face of the unit. If you are still confused feel free to contact Francis Fire Protection Services Ltd for further assistance.