Thermo King 098203, Руководство по обслуживанию

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Refrigeration Maintenance
Introduction
The following procedures involve servicing the refrigeration system. Some of these service procedures
are regulated by Federal, and in some cases, by State and Local laws.
NOTE: All regulated refrigeration service procedures must be performed by an EPA certified
technician, using approved equipment and complying with all Federal, State and Local laws.
Use the Correct Tools
Use the Correct Vacuum Pump
A two-stage (refer to Tool Catalog), three-stage or five-stage pump is recommended for evacuation.
Purging the system with dry nitrogen is recommended before evacuation. Because residual refrigerant
may be present in used vacuum pumps, a new vacuum pump should be used and dedicated strictly as an
R-404a refrigerant pump. Use only recommended vacuum pump oils and change oil after every major
evacuation. Because vacuum pump oils are highly refined to obtain low vacuums, failure to follow these
recommendations may result in acidic conditions that will destroy the pump.
Use Filters and Cartridges
Cleanup devices such as suction line filters and compressor oil filters may be used if they are properly
cleaned and new filters and cartridges are used. All standard petroleum and synthetic compressor oils
must be removed to prevent the contamination of R-404A systems.
Use the Correct Refrigerant Recovery Equipment
Use only refrigerant recovery equipment approved for and dedicated to R-404A recovery.
Detecting Leaks
Leaks can be detected with the use of soap bubbles and with Halogen leak detectors such as model H10G
or model H10N (portable).
Locating Special Service Fittings
Special fittings are used on HFC systems to prevent mixing of non-HFC refrigerants in HFC units. These
fittings are located in three places on MAGNUM refrigeration systems:
• Low side near the compressor suction service valve (or suction adapter)
• High side near the compressor discharge service valve (or discharge manifold)
• Receiver Tank
CAUTION: Use only those service tools certified for and dedicated to R-404A refrigerant
and Polyol Ester based compressor oils (i.e., vacuum pump, refrigerant recovery
equipment, gauge hoses, and gauge manifold set). Residual non-HFC refrigerants or
non-Ester based oils will contaminate HFC systems.