Nortel North American DMS-100 Instruction Manual page 69

Repairing and replacing NT3X90AA cooling units
Summary of Repairing and replacing NT3X90AA cooling units
Start
Y
Dirty
filter?
N
Repair
N
unit on
premises?
Y
Harness
Y
or fan has
faults?
N
Air flow
Y
sensor
has
faults?
N
This flowchart summarizes the
procedure.
Use the instructions that follow this
flowchart to perform the
procedure.
DMS-100 Family NA100 Trouble Locating and Clearing Procedures Volume 2 of 2 LET0015 and up
Trouble locating and clearing procedures (continued)
Two
Y
affected
frames?
N
Clean or
replace filter
Replace
cooling unit
Repair harness
or replace fan
Replace air
flow sensor
Repair N
unit on
premises?
Y
Replace
inverter
Next level of
support
(continued)
Replace
cooling unit
FAN FAIL
N
lamps
out?
Y
End
1-53