Mitsubishi Electric PUZ-A12NKA7 Service Manual page 111

OPERATING PROCEDURE
8. Removing the 4-way valve coil (21S4), LEV coil (LEV(A),
LEV(B))
(1) Remove the service panel. (See Photo 1)
(2) Remove the top panel. (See Photo 1)
(3) Remove the electrical parts box. (See Photo 4)
[Removing the 4-way valve coil]
(4) Remove 4-way valve coil fixing screw (M4 × 6).
(5) Remove the 4-way valve coil by sliding the coil toward
you.
(6) Disconnect the connector 21S4 (green) on the controller
board in the electrical parts box.
[Removing the LEV coil]
(4) Remove the LEV coil by sliding the coil upward.
(5) Disconnect the connectors, LEV A (white) and LEV B
(red), on the controller circuit board in the electrical
parts box.
9. Removing the 4-way valve
(1) Remove the service panel. (See Photo 1)
(2) Remove the top panel. (See Photo 1)
(3) Remove the electrical parts box. (See Photo 4)
(4) Remove 3 valve bed fixing screws (4 × 10) and 4 ball
valve and stop valve fixing screws (5 × 16) and then
remove the valve bed.
(5) Remove 3 right side panel fixing screws (5 × 12) in the
rear of the unit and then remove the right side panel.
(6) Remove the 4-way valve coil. (See Photo 9)
(7) Recover refrigerant.
(8) Remove the welded part of 4-way valve.
Note 1: Recover refrigerant without spreading it in the
air.
Note 2: The welded part can be removed easily by
removing the right side panel.
Note 3: When installing the 4-way valve, cover it with a
wet cloth to prevent it from heating (120°C or
more), then braze the pipes so that the inside
of pipes are not oxidized.
10. Removing the LEV
(1) Remove the service panel. (See Photo 1)
(2) Remove the top panel. (See Photo 1)
(3) Remove the electrical parts box. (See Photo 4)
(4) Remove 3 valve bed fixing screws (4 × 10) and 4 ball
valve and stop valve fixing screws (5 × 16) and then
remove the valve bed.
(5) Remove 3 right side panel fixing screws (5 × 12) in the
rear of the unit and then remove the right side panel.
(6) Remove the LEV.
(7) Recover refrigerant.
(8) Remove the welded part of linear expansion valve.
Note 1: Recover refrigerant without spreading it in the
air.
Note 2: The welded part can be removed easily by
removing the right side panel.
Note 3: When installing the LEV, cover it with a wet
cloth to prevent it from heating (120°C or
more), then braze the pipes so that the inside
of pipes are not oxidized.
OCH636A
PHOTOS & ILLUSTRATION
Photo 8
4-way valve coil
fixing screw
Figure 1
4-way valve
coil (21S4)
High pressure switch
(63H)
Thermistor
<Discharge>(TH4)
Thermistor
<Comp. surface>(TH33)
111
4-way valve
High pressure
switch (63H)
4-way valve
Thermistor
<Ambient>(TH7)
Thermistor
<Liquid>(TH3)
LEV coil (LEV-B)
LEV-B
Thermistor
<Suction> (TH8)
LEV coil (LEV-A)
LEV-A