It’s sad to know that fire alarm panels are not made as well as they used to be. I found another recall of a fire alarm product on the CPSC website. This time it is the Bosch GV4 Fire Alarm Panels.
The NAC module can cause the panels to fail to activate an audible or visual alarm in the event of a fire.
More info if interested: http://www.cpsc.gov/en/Recalls/Recall-Alerts/2014/Bosch-Security-Systems-Recalls-Fire-Control-Panels/