Friedrich ZQ07B10, ZQ05B10 manual Evaporator/Condenser, Capillary Tube

2.4.2 EVAPORATOR/CONDENSER

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 proper connections.

5.Remove the proper coil.

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 refrigeration 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 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 counterclock-

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 21B. 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. Refrigeration cycle 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 clamp on the pinch-off tube. Using a tube cut- ter, cut the pinch-off tube about 2 inches from the pinch-off . Use sil-fos solder and solder the pinch-off tube closed. Turn off the unit, allow unit to sit for a while and then test the leakage of the pinch-off connection.

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