Thermo King CRR-20, Руководство по обслуживанию

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6-4 Gauge Manifold Set Attachment Refrigeration Maintenance and Service Operations
CRR-20 & CRR-40, September 1999
Gauge Manifold Set (With Low Loss
Fittings) Attachment And Purging
Thermo King recommends the use of access valves or self-
sealing, quick disconnect fittings whenever possible to limit
the loss of refrigerant into the atmosphere. A separate gauge
manifold set with low loss fittings (P/N 204-758) should be
dedicated for use with R-134a only. Gauge hoses should also
be dedicated to R-134a.
NOTE: When any of these devices are used, careful-
ly check to ensure that access connections are func-
tioning properly.
Gauge Manifold Set Installation
NOTE: The following procedure purges the gauge
hoses and must be followed when using new gauges
or hoses for the first time. The system should be
operating on Cool (10 psig [69 kPa] or greater suc-
tion pressure) when using this procedure to purge
the low side hose. Gauge hoses may be removed
and re-installed without additional purging so long
as a slight positive pressure remains in the manifold
and lines when removed from the unit.
1. Inspect gauge manifold for proper hose and fitting con-
nections.
2. Clean dirt and moisture from around service ports.
3. Remove small service port caps from suction and dis-
charge service fittings. Save and re-use the caps and seal-
ing washers or gaskets.
4. Rotate both hose coupler hand wheels counterclockwise to
back the stem out of the high and low hose fittings. Then
attach low hose (compound gauge) to the suction line
valve port.
5. With 69 kPa, 0.69 bar, 10 psig or greater pressure in the
low side (unit operating on Cool), open the suction service
manifold hand valve fully. Then rotate the suction hose
fitting hand wheel clockwise to open (depress) the suction
line port valve to the low hose.
6. Slowly screw a 1/2 inch ACME fitting into the low loss
fitting on the manifold’s service (center) line to purge the
suction and service hoses. Remove ACME fitting after
purging.
Purging Gauge Manifold
1. Suction Connection
2. Discharge Connection