Mitsubishi Electric PURY-M200YNW-A1 Service Handbook page 350

[8-13 Parts Replacement Instructions (Outdoor Unit) ]
*Notes on replacing refrigerant circuit components (four-way valve, solenoid valve, and LEV)
Be sure to perform non-oxidized brazing.
Before heating the pipes, wrap the refrigerant circuit components with a wet towel to keep the temperature of the
components from rising above 120°C.
After brazing is done, check that the brazing is done properly and check for leaks before vacuum-drying the pipes.
Direct the brazing torch flame away from the wiring and sheet metals inside the unit not to damage them.
Wet felt sheets listed below (or its equivalent), and place them around the areas to be brazed to protect the heat
exchanger, pipes, and pipe covers from being damaged from the brazing torch flame.
Recommended felt sheets: Spatter felt 50CF-11 (5t x 1 m x 1 m) by TRUSCO Nakayama
Felt sheets that meet the JIS standard (JIS A 1323 type A "Flame retardant testing method for spark droplets of
welding and gas cutting on fabric sheets in construction works")
(4) Remove the braze from the pipe on the left side of four-way valve (21S4a) and between four-way valves (21S4b and
21S4c). (See Figure 5.)
Figure 5
Four-way valve
(21S4a)
Replacement procedure for the four-way valve (21S4a)
(5A) Install a flame-protection plate. (See Figure 6.)
Figure 6
(6A) Remove the braze from the area above four-way valve (21S4a) as shown in Figure 7.
Figure 7
BS_08_L
Four-way valve
(21S4c)
Four-way valve
(21S4b)
Flame-protection plate
*The replacement parts for this part is included with the
replacement kit that contains four-way valve (21S4a).
Remove the plate after replacing four-way valve
(21S4a).
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chapter 8 -