Mitsubishi Electric MXZ-SM72TAM-U1 Service Manual page 114

2. Remove 4-way valve coil fixing screws (M5 × 7).
3. Remove the 4-way valve coil by sliding the coil toward you.
4. Loosen the clamp or band for the lead wire of the electrical parts box and the separator.
5. Disconnect the connector 21S4 (green) on the outdoor multi controller circuit board in the electrical parts box.
8. Removing the 4-way valve
1. Remove the service panel. (See Photo 1)
2. Remove the top panel. (See Photo 1)
3. Remove the cover panel front. (See Photo 1)
4. Remove the cover panel rear. (See Photo 1)
5. Remove the side panel R. (See Photo 1)
6. Remove the electrical parts box. (See Photo 5)
7. Remove 4 ball valve and stop valve fixing screws (5 × 16) then valve bed fixing screws (5 × 12) and remove the
valve bed. (See Photo 8)
8. Remove the 4-way valve coil.
9. Recover refrigerant.
10. Remove the welded part of 4-way valve.
Notes:
• Recover refrigerant without spreading it in the air.
• When installing the 4-way valve, cover it with a wet cloth to prevent it from heating (248°F [120°C] or more), then
braze the pipes so that the inside of pipes are not oxidized.
• Be careful not to expose the fusible plug to the braze torch flame or transfer heat to it. The temperature of the fusible
plug must not become 140°F (60°C) or more while working. Protect the fusible plug with a wet cloth when neces-
sary. (The fusible plug breaks at 158°F [70°C]).
Photo 10
4-way valve coil
(21S4)
9. Removing the bypass valve coil (SV1 and SV3) and the bypass valve
1. Remove the service panel. (See Photo 1)
2. Remove the top panel. (See Photo 1)
3. Remove the cover panel front. (See Photo 1)
4. Remove the cover panel rear. (See Photo 1)
5. Remove the side panel R. (See Photo 1)
6. Remove the bypass valve coil fixing screw (M4 × 6).
7. Remove the bypass valve coil by sliding the coil upward.
8. Disconnect the connector SV1 (gray) and SV3 (black) on the multi controller circuit board in the electrical parts box.
(See Photo 10 and 11)
9. Remove the electrical parts box to remove SV1. (See Photo 5)
10. Recover refrigerant.
11. Remove the welded part of bypass valve.
Notes:
• Recover refrigerant without spreading it in the air.
• When installing the bypass valve, cover it with a wet cloth to prevent it from heating (212°F [100°C] or more), then
braze the pipes so that the inside of pipes are not oxidized.
• Be careful not to expose the fusible plug to the braze torch flame or transfer heat to it. The temperature of the fusible
plug must not become 140°F (60°C) or more while working. Protect the fusible plug with a wet cloth when neces-
sary. (The fusible plug breaks at 158°F [70°C]).
OCH800A_114
4-way valve
4-way valve coil
fixing screw
Bypass valve
coil (SV3)