Manitowoc J-1300, Service Manual

Page: 156 / 165

Section 7 Refrigeration System
7-51
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.
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.
Important
Dry nitrogen is recommended for this procedure.
This will prevent CFC release.
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 is no leak.
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. Disassemble the hot gas solenoid valve. If
burnout deposits are found inside the valve,
install a rebuild kit, and replace the TXV and
harvest pressure regulating valve.
4. Wipe away any burnout deposits from suction and
discharge lines at compressor.
5. Sweep through the open system with dry nitrogen.
Important
Refrigerant sweeps are not recommended, as they
release CFC’s into the atmosphere.
7. Install a new compressor and new start
components.
8. Install a suction line filter-drier with acid and
moisture removal capability (P/N 89-3028-3).
Place the filter drier as close to the compressor as
possible.
9. Install an access valve at the inlet of the suction
line drier.
10. Install a new liquid line drier.
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