Thermo King CRR-40 119, Руководство пользователя

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Refrigeration Maintenance and Service Operations
126
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,
carefully check to ensure that access
connections are functioning 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 suction 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 connections.
2. Clean dirt and moisture from around service
ports.
3. Remove small service port caps from suction
and discharge service fittings. Save and re-use
the caps and sealing 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.
7. Close the suction service manifold hand valve
fully to center port.
8. Attach high side hose (pressure gauge) to the
discharge service line port.
9. Open discharge service manifold hand valve
fully. Then rotate discharge fitting hand wheel
clockwise to open (depress) discharge line
port valve to the high hose.
10. Slowly screw a 1/2 inch ACME fitting into the
manifold’s service (center) line to purge the
high and service hoses. Remove ACME fitting
after purging.
11. Close discharge service manifold hand valve
fully to center port. You are now ready to use
the gauge manifold to check system pressures
or perform MOST service procedures.
NOTE: These gauges may be removed and
reinstalled without additional purging so
long as a slight positive pressure remains in
the manifold and hoses when removed from
the unit.
1. Suction Connection
2. Discharge Connection
Figure 38: Purging Gauge Manifold
AJA1310