Mitsubishi Electric PURY-P120TJMU-A, Service Handbook, Page: 354 / 411

[
IX
Troubleshooting ]
- 345 - HWE0913A GB
3. Solenoid valve block ASSY (SV4a, SV4b, SV4d), Check valve (CV4a, CV6a, CV8a, CV9a) replacement instructions
* Following instructions show procedures for replacing service parts for Solenoid valve block ASSY (SV4a, SV4b,
SV4d), Check valve (CV4a, CV6a, CV8a, CV9a). Replace them properly according to the procedures.
1. Applicable models
• PURY-P120, P144TJMU-A (-BS), PURY-P120, P144YJMU-A (-BS)
2. Parts to be serviced, Set-content
Following instructions are applicable to 1-3 service parts on the table below.
NO. Parts to be serviced
1 Solenoid valve block ASSY
(SV4a, SV4b, SV4d)
2 Check valve (CV4a, CV8a, CV9a)
3 Check valve (CV6a)
Things required for replacing
Item
Solenoid valve block service parts set
[Set-content]
•
Replacement instructions
• Solenoid valve block ASSY
Numbers
1
1
1
Service parts replacement instructions set
[Set-content]
•
Replacement instructions
• Check valve
1
1
1
3. Procedures
* Precautions for starting replacement
• Check that the main power supply is OFF.
• Check that no refrigerant is in the outdoor unit.
Remove each part according to the 1)-3) procedures on the next page before replacing service parts.
Mount the removed parts back in place in a reversed procedures of 1)-3) on the next page after replacing service
parts.
(1) Solenoid valve block ASSY (SV4a, SV4b, SV4d) replacement procedures
To remove Solenoid valve block ASSY
Remove the solenoid valve block coil cover, solenoid valve coil, and peripheral cables.
Remove the M5 screws that are holding the solenoid valve block supporting plate and the base.
Debraze A-G parts (total 7 places).
Do not damage heat exchanger fins and peripheral piping devices when removing the Solenoid valve block ASSY.
Remove the M5 screws that are holding the solenoid valve block and the solenoid valve block supporting plate.
To install Solenoid valve block ASSY
Remove the brazed pipe at section H in the figure.
Fix the solenoid valve block assembly and the supporting plate in place with the M5 screws.
Using caution not to damage the heat exchanger fins and the surrounding pipes, hold the replacement solenoid valve block
assembly inside the unit, and then fix the solenoid valve block supporting plate and the base in place with the M5 screws.
Braze the seven spots labeled A through C in the figure.
Mount the solenoid valve block coil cover, solenoid valve coil, and peripheral cables back in place.
* Precautions for replacing Solenoid valve block ASSY
• Be sure to perform no-oxidation brazing when brazing.
• Before heating the pipes, place a wet towel on the solenoid valve block to keep its temperature below 120ºC [248ºF].
• After brazing, check the condition around the brazing. After confirming no leakage, evacuate the air inside. (*1)
• Perform carefully with the flame direction so that it does not burn cables and plates etc. in the unit.
• Remove the brazing part protecting heat exchanger fins from burning, and replace the service parts.
*1: Refer to Chapter I [8] Vacuum Drying (Evacuation) for detailed procedure.
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