Service manual

Section 7 Refrigeration System
Part No. 80-1206-3 7-39
Mild System Contamination Cleanup Procedure
1. Replace any failed components.
2. If the compressor is good, change the oil.
3. Replace the liquid line drier and suction filter.
NOTE: If the contamination is from moisture, use heat
lamps during evacuation. Position them at the
compressor, condenser and evaporator prior to
evacuation. Do not position heat lamps too close to
plastic components, or they may melt or warp.
4. 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 psi.
B. Pull vacuum to 500 microns. Break the vacuum
with dry nitrogen and sweep the system.
Pressurize to a minimum of 5 psi.
C. Change the vacuum pump oil.
D. Pull vacuum to 250 microns. Run the vacuum
pump for 1/2 hour on self-contained models, 1
hour on remotes.
NOTE: You may perform a standing vacuum test to
make a preliminary leak check. You should use an
electronic leak detector after system charging to be sure
there are no leaks.
5. Charge the system with the proper refrigerant to the
nameplate charge.
6. Operate the ice machine.
Severe System Contamination Cleanup Procedure
1. Remove the refrigerant charge.
2. Remove the compressor.
3. Cut copper tubing at the outlet of the cool vapor
valve. If burnout deposits are found inside the
tubing, replace the cool vapor valve, 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.
6. Install a new compressor and new start components.
7. Replace existing suction line filter drier in front of
accumulator.
8. Install a new liquid line drier.
Continued on next page …
Important
Dry nitrogen is recommended for this procedure.
This will prevent CFC release.
Important
Refrigerant sweeps are not recommended, as they
release CFC’s into the atmosphere.