4-40. REMOVE/INSTALL GAS ALARM SYSTEM - continued.
Loosen terminals 1, 3, 8, on terminal board no. 1 and 19, A1 C1, and R1 on TB2, tag for reconnection and
disconnect terminal wires. Disconnect ground wire (green) last.
g. Loosen two conduit fittings and disconnect flexible conduit to buzzer and power input.
h. Reinstall circuit board, shut and latch alarm panel, and close cover.
Remove four gas alarm mounting screws, lockwashers, and flat washers.
Carefully remove defective gas alarm.
2. Remove Gas Alarm Detector Element. See figure 4-33.
a. Power input cable to laboratory disconnect.
b. Loosen set screw on shield assembly. Unscrew and remove shield assembly.
c. Unplug defective element.
3. Remove Gas Alarm Buzzer. See figure 4-32.
a. Disconnect power input cable to laboratory.
b. Remove cover plate screws and remove cover from junction.
c. Tag for reconnection and remove two wires from buzzer.
d. Remove mounting collar and remove defective buzzer.
Install Gas Alarm. See figure 4-31.
a. Carefully place new gas alarm into position on wall.
b. Install four mounting screws, flatwasher and lockwashers.
c. Unlatch and open cover, loosen captive screw and swing panel out, and remove circuit board.
d. Connect flexible conduits from buzzer and power input fitting.