The DBM21 doorbell module allows a Panasonic compatible third-party doorbell/intercom unit to provide communications and door bell chimes within the W.H.E.N. system. When the doorbell is pressed, a chime is sounded in all enabled KP21 keypad zones. The user in an enabled room can then talk to the guest at the door by pressing and holding the talk button on the KP21 keypad. The door station then goes into an audio/video monitoring mode and the guest may speak to the station that initiated the talk back function. Locking and unlocking doors may also be controlled by the keypad. Up to six doorbell stations may be controlled by KP21 keypads located throughout the home.