System Contamination Clean-Up - Manitowoc S Service Manual

Section 7

SYSTEM CONTAMINATION CLEAN-UP

General
This section describes the basic requirements for
restoring contaminated systems to reliable service.
Manitowoc Ice, Inc. assumes no responsibility for
the use of contaminated refrigerant. Damage
resulting from the use of contaminated refrigerant is
the sole responsibility of the servicing company.
Determining Severity Of Contamination
System contamination is generally caused by either
moisture or residue from compressor burnout entering
the refrigeration system.
Inspection of the refrigerant usually provides the first
indication of system contamination. Obvious moisture or
an acrid odor in the refrigerant indicates contamination.
Symptoms/Findings
No symptoms or suspicion of contamination
Moisture/Air Contamination symptoms
Refrigeration system open to atmosphere for longer than 15
minutes
Refrigeration test kit and/or acid oil test shows contamination
Leak in water-cooled condenser
No burnout deposits in open compressor lines
Mild Compressor Burnout symptoms
Oil appears clean but smells acrid
Refrigeration test kit or acid oil test shows harmful acid content
No burnout deposits in open compressor lines
Severe Compressor Burnout symptoms
Oil is discolored, acidic, and smells acrid
Burnout deposits found in the compressor and lines, and in
other components
Part Number 80-1480-3
Important
Contamination/Cleanup Chart
If either condition is found, or if contamination is
suspected, use a Total Test Kit from Totaline or a similar
diagnostic tool. These devices sample refrigerant,
eliminating the need to take an oil sample. Follow the
manufacturer's directions.
If a refrigerant test kit indicates harmful levels of
contamination, or if a test kit is not available, inspect the
compressor oil.
1. Remove the refrigerant charge from the ice
machine.
2. Remove the compressor from the system.
3. Check the odor and appearance of the oil.
4. Inspect open suction and discharge lines at the
compressor for burnout deposits.
5. If no signs of contamination are present, perform an
acid oil test.
Check the chart below to determine the type of cleanup
required.
Required Cleanup Procedure
Normal evacuation/recharging procedure
Mild contamination cleanup procedure
Mild contamination cleanup procedure
Severe contamination cleanup procedure
Refrigeration System
7-53