Mitsubishi Electric PURY-HP144, Service Handbook

Page: 324 / 398

[8-13 Parts Replacement Instructions ]
HWE18220_GB chapter 8 -
83
8 Troubleshooting Based on Observed Symptoms
(2) TNU
[Removing the duct]
Unscrew the two screws indicated with arrows in Figure
1-a, and pull up the duct to remove it.
(Figure 1-b shows the unit after the duct was removed.)
[Figure 1-b]
[Figure 1]
[Figure 2]
[Figure 3]
[Figure 3-a]
[Figure 4]
[Figure 1-a]
[Removing the refrigerant cooling pipes]
Remove the braze at the two areas indicated with arrows in Figure 2.
Before removing the pipes, collect the refrigerant.
Refer to "Notes on replacing refrigerant circuit components."
[Removing the remaining relevant components]
Unscrew the four screws indicated with arrows in Figure 3.
The arrow indicated with dotted lines is located where indicated in Figure 3-a.
Pull the unscrewed part forward, and unhook the part indicated with Arrow to
remove the part from the base of the unit.
*Notes on replacing the control box (when replacing the refrigerant cooling pipes)
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")
A
B
To remove the rest of the components from the pillar,
unscrew the two screws indicated with Arrow in
Figure 4.
C
Ⓐ
Ⓐ
Ⓐ
Ⓑ
Ⓐ
Ⓒ
Ⓒ