TM 10-5410-228-24
2.8
UNIT LEVEL TROUBLESHOOTING PROCEDURES Continued.
8.
NBC FAN `PRESSURE LOW' INDICATOR DOES NOT COME ON AND AUDIBLE ALARM DOES
NOT SOUND WHEN NBC FAN SWITCH IS FIRST TURNED ON MUTE SWITCH OFF, `NBC FAN
ON' INDICATOR ON Continued.
1
Check for 24 Vdc between
connector socket H to ground.
Apply power to system.
Push NBC fan to ON.
Is
Replace relay A4K8
24 Vdc
Yes
(see para 2.13.25).
present?
No
Repair wiring as required.
2-40
