Mitsubishi Electric PUHY-M200YNW-A1 Service Handbook page 340

[8-13 Parts Replacement Instructions ]
(24B) Mount four-way valve (21S4b) to the pipe below four-way valve (21S4b) and in the middle. A total of five areas require
brazing, including the area indicated in (23B) and the areas indicated in Figure 23.
Mount four-way valve (21S4b) horizontal to four-way valve (21S4a) as shown in (15A).
Figure 23
(25B) Install the pipe below four-way valve (21S4b) and on the front by brazing at the two areas shown in Figure 24.
Re-place the rubber spacer.
Figure 24
This step completes the replacement procedure for four-way valve (21S4b). Re-place the solenoid valve and LEV assembly
that were removed in step (8) and all the pipe covers that were removed during the maintenance work as they were.
BS_08_E
When installing four-way valve
(21S4b), first braze the pipe
outside the unit and then install it
to the unit.
Reinstall these pipes.
chapter 8 -
85