Mitsubishi Electric PUZ-WZ50VAA Service Manual page 76

OPERATING PROCEDURE
3. Removing the fan motor (MF1)
(1) Remove the service panel. (See Photo 1-1)
(2) Remove the top panel. (See Photo 1-1)
(3) Remove the cover panel fixing screws (1 for front and 1 for
right side/ 5 × 12), then slide the cover panel upward to remove
it. (See Photo 1-1)
(4) Remove the wire grill fixing screws (6 for front/ 5 × 12), then
slide the wire grill upward to remove it. (See Photo 1-1)
(5) Remove the screw of nut (1 for front/ M6), then slide the pro-
peller fan forward to remove it. *2 (See Photo 3-1)
(6) Remove the electrical parts box. (See Photo 2-1, 2-2, 2-4, 2-5)
(7) Remove the front panel fixing screws (4 for front/ 5 × 12), then
slide the front panel forward to remove it. (See Photo 3-1)
(8) Loosen the clamps for the lead wire on motor support and
separator. (See Photo 3-2)
(9) Remove the insulation which attached over the edge cover.
(See Photo 3-2)
(10) Remove the fan motor fixing screws (4 for front/ 5 × 25) to
remove the fan motor.*1 (See Photo 3-3)
Note 1: When attaching the fan motor, make sure to route the
cable through the hook below the fan motor and fix
firmly with the clamp.
Note 2: Tighten the propeller fan with a torque of 5.7 ± 0.3 N·m.
4. Disassembling the electrical parts box
(1) Remove the electrical parts box. (See Photo 2-1, 2-2, 2-4, 2-5)
[Power Board]
(2) Remove the top cover fixing screws (8 for top/ 5×12), then
remove the top cover of the electrical parts box. (See Photo
2-4, 4-1)
(3) Disconnect all the connectors on the power circuit board. (See
Photo 4-3)
(4) Remove the power board fixing screws (5 for front/ 3×12),
then remove the mold casing of the power board. (See Photo
4-4)
(5) Remove the IPM fixing screws (4 for front/ 3×12, 2 for front/
4×12 ). (See Photo 4-4)
(6) Slide the power circuit board to remove it.
[THERMISTOR (HEAT SINK)]
(7) Remove the thermistor <Heat sink> (TH8) fixing screw ( 1 for
front/ 3 × 12) to remove the thermistor <Heat sink>(TH8).(See
Photo 4-5)
[Control Circuit Board]
(8) Disconnect the all lead wires from the clamps and the all con-
nectors on the controller circuit board. (See Photo 4-6)
(9) To remove the circuit board, release it from the support.
[TERMINAL BLOCK]
(10) Remove the lead wire L/N, CX, Earth, CNS on the terminal
block. (See Photo 4-7)
(11) Remove the terminal block fixing screw. (See Photo 4-7)
[REACTOR]
(12) Disconnect the lead wire L/N, CNDC, CNAC from edge cover.
(Photo 4-8)
(13) Remove the insulation from the electrical box. (See Photo
4-9)
(14) Remove the screws on the electrical box. (4 for right/ 4×10) ,
then slide the plate upward to remove it.
(See Photo 4-10, 4-11)
(15) Remove the all connectors of the reactor. (See Photo 4-12)
(16) Remove the reactor fixing screws (4 for right/ 4×10). (See
Photo 4-12)
Note 1: When reassembling the electrical parts box, make sure the wirings are
correct.
Note 2: When reassembling the electrical parts box, make sure whether the seal-
ing materials of top cover degraded or are damaged. If the sealing materi-
als degraded or are damaged, replace it with a new one.(See photo 4-2)
OCH816
PHOTOS/FIGURES
Photo 3-1
Photo 3-2
Photo 3-3
Photo 4-1
Photo 4-3
Mold casing of the power board
Power board
Photo 4-4
Power board fixing screws
Power board fixing screws
Photo 4-5
76
Front panel
Propeller
Nut
Front panel
fixing screws
Clamps for
the lead wire
Insulation
Fan motor fixing screws
Photo 4-2
Sealing materials of top
cover plate
IPM fixing screws
Thermistor (TH8)
fixing screw
Continued to the next page.