An aspirating smoke detector device , comprising: a wireless module ; a buzzer configured to buzz at a plurality of different frequencies; and a controller ; wherein: the wireless module is configured to receive a connection request from a mobile device ; and the controller is configured to: generate a temporary key, TK, having a plurality of digits, wherein each digit of the TK can have a value between 0 and 9; cause the buzzer to produce a buzzer signal including a plurality of portions corresponding to the plurality of digits of the TK, wherein each portion has one frequency of the plurality of different frequencies, and wherein each of the plurality of different frequencies corresponds to a different value of the corresponding digit of the TK between 0 and 9; receive, via the wireless module , an indication of the TK determined by the mobile device based on the buzzer signal; and communicate with the mobile device to complete a pairing with the mobile device using the TK. a wireless module ; a buzzer configured to buzz at a plurality of different frequencies; and a controller ; wherein: the wireless module is configured to receive a connection request from a mobile device ; and the controller is configured to: generate a temporary key, TK, having a plurality of digits, wherein each digit of the TK can have a value between 0 and 9; cause the buzzer to produce a buzzer signal including a plurality of portions corresponding to the plurality of digits of the TK, wherein each portion has one frequency of the plurality of different frequencies, and wherein each of the plurality of different frequencies corresponds to a different value of the corresponding digit of the TK between 0 and 9; receive, via the wireless module , an indication of the TK determined by the mobile device based on the buzzer signal; and communicate with the mobile device to complete a pairing with the mobile device using the TK. the wireless module is configured to receive a connection request from a mobile device ; and the controller is configured to: generate a temporary key, TK, having a plurality of digits, wherein each digit of the TK can have a value between 0 and 9; cause the buzzer to produce a buzzer signal including a plurality of portions corresponding to the plurality of digits of the TK, wherein each portion has one frequency of the plurality of different frequencies, and wherein each of the plurality of different frequencies corresponds to a different value of the corresponding digit of the TK between 0 and 9; receive, via the wireless module , an indication of the TK determined by the mobile device based on the buzzer signal; and communicate with the mobile device to complete a pairing with the mobile device using the TK. generate a temporary key, TK, having a plurality of digits, wherein each digit of the TK can have a value between 0 and 9; cause the buzzer to produce a buzzer signal including a plurality of portions corresponding to the plurality of digits of the TK, wherein each portion has one frequency of the plurality of different frequencies, and wherein each of the plurality of different frequencies corresponds to a different value of the corresponding digit of the TK between 0 and 9; receive, via the wireless module , an indication of the TK determined by the mobile device based on the buzzer signal; and communicate with the mobile device to complete a pairing with the mobile device using the TK. <EOS>