Mitsubishi Electric HP120TNU-A Service Handbook page 315

[8-13 Parts Replacement Instructions ]
(7) Cut the bands on the TH3 wiring, and remove the pipe covers and rubber spacer on the heat-exchanger side. (See Figure 7.)
Figure 7
(8) Remove the pipe covers and the thermal insulation on the compressor. (See Figure 8.)
Figure 8
*Notes on replacing refrigerant circuit parts (check valve block assemblies, four-way valves, solenoid valves, and LEVs)
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")
Check valve block replacement procedure
(9) Remove the braze at the three areas circled in the figure to remove LEV9 assembly. (See Figure 9.)
LEV9
74
- chapter 8
Rubber spacer and band
Remove the two pipe covers.
* Save the pipe covers for later
use.
Remove the
braze here.
Figure 9
TH3 wiring, pipe cover
Remove the pipe cover adjacent to the brazed area of the
heat exchanger.
*Save the pipe covers for later use.
Thermal insulation
* Save the thermal insulation for later use.
LEV9
Remove the
braze here.
LEV9 assembly
Rubber spacer and band
Remove the
braze here.
HWE18220_GB