Toshiba MMY-MAP0804FT7(Z), Service Manual, Page: 276 / 333

– 276 –
4-way valve
- detachment/
attachment
(continued)
MAP1204FT
∗
MAP1404FT ∗
No. Part to be replaced Work procedure Remarks
9
PMV
4) Brazed point
4) Brazed point
5) Screw
5) Brazed point
7) Brazed point
6) Cutting line
(2 pieces at
front side)
4-way valve
Insert a torch
5) Brazed point
10) Bypass
assembly
10) Bypass
assembly
4-way valve for pilot
Front side
14) PMV4
PMV assembly
Cut off the upper pipe
of 4-way valve at 2
positions.
Remove one pipe at
the brazed section.
Remove the brazed sections
at 2 positions at the left side
of strainer.
Remove a brazed section at
rear side of PMV assembly.
4-way valve
Remove a brazed
section of pipe at the
lower side of 4-way
valve
5) Discharge gas
assembly
New 4-way
valve
WARNING
Wear a pair of gloves.
Otherwise, you will risk an injury involving a
replacement part or some other object.
Before starting the work, be sure to recover the refrigerant of
outdoor unit by removing it with a refrigerant recovery device.
1. Detachment
1) Remove the lower cabinet (front side).
2) Remove the inverter box in accordance with the
dismantling instructions.
3) Disconnect the 4-way valve coil and PMV coils (3
pieces) and get all wiring located near the 4-way valve
out of the way.
4) Remove brazed points (2 locations) for the PMV
assembly, which is placed in front of the 4-way valve.
* Provide adequate cover for the PMV proper to
protect it from overheating.
5) Take off screws (2 pcs) which are fixing the valve of the
discharge gas valve assembly at the front side of 4-way
valve and also remove the brazed section (1 point).
6) For upper pipes of 4-way valve (2 pcs at front side),
use a saw, or so on and cut at lower side of the brazed
section at upper brazed section of 4-way valve.
7) Remove brazed section (1 point) of the pipe of bypass
circuit which arranged at left side of 4-way valve. Insert
a torch into the right side of the front side of the
outdoor unit and then carry out welding work.
8) Remove the brazed section (1 point) of the lower pipe
of 4-way valve.
9) Take off the pipe remained when pipe was cut off in
item 6).
10) Move the bypass assembly removed from the old 4-
way valve to a new 4-way valve.
11) Mount a new 4-way valve.
* Be sure to cure sufficiently so that overheat of 4-way
valve is avoided.
In this time, insert the connecting pipes surely into 4-
way valve; otherwise wax choking or leakage is caused.
12) Mount the discharge gas assembly removed in item 5).
* Cure sufficiently so that gas valve is not heated.
13) Mount PMV assembly removed in item 4).
* Cure sufficiently so that PMV is not heated.
14) Return the coil removed in item 3) to the original
position and then return various wiring to original
position.
* When mounting PMV, refer to the right figure so that
there is no miss-mounting.
15) According to section, How to mount inverter box
(p.282), mount the inverter box.
16) Attach the lower cabinet.
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