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2.4.2 EVAPORATOR
1. Remove the cabinet.
2. Discharge the refrigerant by using a refrigerant recovery system.
3. Remove the air guide upper. (Refer to Section
2.2.1)
4. After discharging the refrigerant completely, unbraze the interconnecting tube at the condenser connections.
5. Remove the evaporator.
6. Re-install by referring to the procedures above.
2.4.3 CAPILLARY TUBE
1. Remove the cabinet.
2. Discharge the refrigerant by using a refrigerant recovery system.
3. Remove the air guide upper. (Refer to Section
2.2.1)
4. After discharging the refrigerant completely, unbraze the interconnecting tube of the capillary tube.
5. Remove the capillary tube.
6. Re-install by referring to the procedures above.
NOTES
Replacement of the refrigeration cycle.
1. When replacing the refrigerating cycle, be sure to discharge the refrigerant by using a refrigerant recovery system.
2. After discharging the unit completely, remove the desired components, and unbraze the pinch-off tubes.
3. Solder service valves into the pinch-off tube ports, leaving the valves open.
4. Solder the pinch-off tubes with service valves.
5. After completing the above procedures, the valve must be closed and left in place on the system for any subsequent procedures.
6. Evacuate as follows:
6-1. Connect the vacuum pump, as illustrated in figure 21A.
6-2. Start the vacuum pump. Slowly open manifold valves A and B with two full turns counterclockwise and leave the valves closed.
The vacuum pump is now pulling through valves A and B up to valve C by means of manifold and the entire system.
CAUTION : If high vacuum equipment is used, just crack valves A and B for a few minutes, then open slowly with the two full turns counter-clock-
—10— wise. This will keep oil from foaming and being drawn into the vacuum pump.
6-3. Operate the vacuum pump for 20 to 30 minutes, until 600 micron vacuum is obtained.
Close valves A and B and observe vacuum gauge for a few minutes.
A rise in pressure would indicate a possible leak or moisture remaining in the system.
With valves A and B closed, stop the vacuum pump.
6-4. Remove the hose from the vacuum pump and place it on the charging cylinder. See figure
23B. Open valve C.
Discharge the line at the manifold connection.
6-5. The system is now ready for final charging.
7. Recharge as follows:
7-1. Rotary compressor systems are charged from the high-side. If the total charge cannot be put in the high-side, the balance will be put in the suction line through the access valve which is installed as the system is opened.
7-2. Connect the charging cylinder as shown in figure 21B. With valve C open, discharge the hose at the manifold connection.
7-3. Open valve A and allow the proper charge to enter the system. Valve B is still closed.
7-4. If more charge is required, the high-side will not take it. Close valve A.
7-5. With the unit running, open valve B and add the balance of the charge. a. Do not add the liquid refrigerant to the lowside. b. Watch the low-side gauge, allow pressure to rise to 30 lbs. c. Turn off valve B and allow the pressure to drop. d. Repeat steps B and C until the balance of the charge is in the system.
7-6. When the unit is operating correctly, use the pinch-off tool with the unit still running and the clamp on the pinch-off tube. Using a tube cutter, cut the pinch-off tube about 2 inches from the pinch-off tool. Use sil-fos solder and solder the pinch-off tube closed. Turn off the unit, allow setting for a while and then test the leakage of the pinch-off connection.
Equipment needed: Vacuum pump, charging cylinder, manifold gauge, brazing equipment, pinch-off tool capable of making a vapor proof seal, leak detector, tubing cutter, hand tools to remove components and service valve.
COMPOUND GAUGE
MANIFOLD
GAUGE
B A
CONDENSER
(HIGH PRESSURE SIDE)
COMPRESSOR
SEE INSETS
BELOW
EVAPORATOR
(LOW PRESSURE SIDE)
CAPILLARY TUBE
B
A
EXTERNAL VACUUM PUMP
B
LO HI CHARGING CYLINDER
A
Figure 21A-Pulling Vacuum Figure 21B-Charging
C
—11—
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