Welbilt Koolaire KD0270A, Technician'S Handbook, Page: 115 / 136

Part Number STH047 Rev01 10/18 115
SEVERE SYSTEM CONTAMINATION CLEANUP
PROCEDURE
1. Remove the refrigerant charge.
2. Remove the compressor.
3. Disassemble the harvest solenoid valve. If burnout
deposits are found inside the valve, install a rebuild
kit, and replace the TXV and head pressure control
valve.
4. Wipe away any burnout deposits from suction and
discharge lines at compressor.
5. Sweep through the open system with dry nitrogen.
Importar
Refrigerant sweeps are not recommended, as they
release CFC into the atmosphere.
Dry nitrogen is recommended for this procedure. This
will prevent CFC release.
6. Install a new compressor and new start components.
7. Install suction line filter-drier in front of compressor.
8. Install a new liquid line drier.
9. Follow the normal evacuation procedure, except
replace the evacuation step with the following:
A. Pull vacuum to 1000 microns. Break the vacuum
with dry nitrogen and sweep the system.
Pressurize to a minimum of 5 psig.
B. Change the vacuum pump oil.
C. Pull vacuum to 500 microns. Break the vacuum
with dry nitrogen and sweep the system.
Pressurize to a minimum of 5 psig.
D. Change the vacuum pump oil.
E. Pull vacuum to 500 microns. Run the vacuum
pump for 1 additional hour.
10. Charge the system with the proper refrigerant to the
nameplate charge.