Carrier 69NT40-561-300, Руководство по эксплуатации и обслуживанию

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T-365 7–2
When the Suction Pressure Valve is open and the Discharge Pressure Valve shut, the system can be charged
through the Utility Connection. Oil can also be added to the system.
A R-134a manifold gauge/hose set with self-sealing hoses (see Figure 7.2 ) is required for service of the models
covered within this manual. The manifold gauge/hose set is available from Carrier Transicold. (Carrier Transicold
part number 07-00294-00, which includes items 1 through 6,
Figure 7.2 .)
If the manifold gauge/hose set is new or was exposed to the atmosphere, it will need to be evacuated to remove
contaminants and air as follows:
1. Backseat (turn counterclockwise) both field service couplings (see Figure 7.2 ) and midseat both hand
valves.
2. Connect the yellow hose to a vacuum pump and refrigerant 134a cylinder.
3. Evacuate to 10 inches of vacuum and then charge with R-134a to a slightly positive pressure of 0.1 kg/cm
2
(1.0 psig).
4. Frontseat both manifold gauge set valves and disconnect from cylinder. The gauge set is now ready for use.
Figure 7.2 Manifold Gauge/Hose Set
1. RED Refrigeration and/or Evacuation Hose
(SAE J2196/R-134a)
2. Hose Fitting (0.5-16 Acme)
3. YELLOW Refrigeration and/or Evacuation
Hose (SAE J2196/R-134a)
4. Hose Fitting with O-ring (M14 x 1.5)
5. High Side Field Service Coupling (Red Knob)
6. BLUE Refrigeration and/or Evacuation Hose
(SAE J2196/R-134a)
7. Low Side Field Service Coupling (Blue Knob)
- - - - -
7.3 SERVICE CONNECTIONS
The compressor suction, compressor discharge, and the liquid line service valves (see Figure 7.3 ) are provided
with a double seat and an access valve which enables servicing of the compressor and refrigerant lines.
Turning the valve stem clockwise (all the way forward) will frontseat the valve to close off the line connection and
open a path to the access valve. Turning the stem counterclockwise (all the way out) will backseat the valve to
open the line connection and close off the path to the access valve.
With the valve stem midway between frontseat and backseat, both of the service valve connections are open to the
access valve path.
For example, the valve stem is first fully backseated when connecting a manifold gauge to measure pressure.
Then, the valve is opened 1/4 to 1/2 turn to measure the pressure.
To Low Side
Access Valve To High Side
Access Valve
1
2
3
2
4
5
6
4
7