TM 10-5410-228-24
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.
2
Set ESS MODE selector switch to HEAT.
Set ESS MODE selector switch to COOL.
Set ESS MODE selector switch to VENT.
Observe ALARM MUTE indicator in each
position.
No
Does indicator come on
(blue)?
Yes
Set POWER MODE selector switch to INT.
Set ESS MODE selector switch to OFF.
Replace ESS MODE selector
Turn ECV OFF.
switch (see para 2.13.23).
Tag power panel and cab area.
Set NBC/VENT circuit breaker A4CB2 to ON.
Test for continuity between terminals.
No
Replace circuit breaker
Does continuity exist?
A4CB2.
Yes
Do a continuity check of the
electrical wiring from A4CB2 to
A4DS9 per Appendix F, Fig. F-9,
sheet 5.
Repair wiring as required.
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