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 20A.
6-2. Start the vacuum pump. Slowly open manifold valves A and B with two full turns counter- clockwise 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- wise. This will keep oil from foaming and being drawn into the vacuum pump.
6-3. Operate the vacuum pump for 20 to 30 min- utes, 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 fig- ure 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 low- side.
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 cut- ter, 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 leak- age of the pinch-off connection.
