Nortel North American DMS-100, Instruction Manual

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-8 Trouble locating and clearing procedures
297-8021-544 Standard 15.01 March 2003
Repairing and replacing NT3X90AF cooling units
(continued)
27 If you find a bad harness, replace the harness. Tighten any loose
connections.
28 Replace the fuses at the front of the cooling unit.
29 Cut the two tie wraps that secure the power cord to the fan.
30 Remove the four screws and washers that secure the fan to the cooling unit.
31 Disconnect the power cord at the fan terminals.
32 Remove the fan that has faults.
33 Connect a new fan to the power cord.
34 Mount the new fan. Install the fan so that air flows toward the top, as indicated
on the label. Secure the new fan with screws, spacers, nuts, and washers.
35 Use the new tie wraps to secure the power cord to the fan.
36 Inspect the fan operation.
37 Ease the cooling unit completely into into the frame.
38 Install the eight screws that secure the mounting flanges on the sides of the
cooling unit to the frame. To insert the screws, use a 5/16-inch ratchet and
extension.
39 Reinstall the side rail covers on the front of the frame.
40 Reinstall the air intake grill and filter assembly at the front of the cooling unit.
41 Turn OFF the FAN FAIL OVERRIDE switch on the FSP.
42 Go to step 44.
If Do
all fans work correctly and the
FAN FAIL lamp is off step 37
one or more fans do not work step 29
If all fans Do
work correctly Step 37
do not work correctly Step 43