Black Box CRDX-A-FS-12KW Manuale Utente

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Page 121

Chapter 5: Maintenance

5.3.3.2 Standard Cleanout Procedure

1. Turn off power to unit at the main power disconnect switch.

2. Remove the old compressor and install the new compressor.

3. Remove the liquid line drier and install an oversized liquid line filter-drier (one size larger than the normal selection size).

4. Evacuate the system according to standard procedures. Normally, this will include the use of a high-vacuum pump and a low-

vacuum micron gauge for measuring the vacuum obtained.

5. Recharge the system.

6. Turn on the power at the main power disconnect switch and start the system.

5.3.3.3 Burn-Out/Acidic Cleanup Procedure

1. These systems should be cleaned using the suction line filter-drier method.

2. Turn off power to the unit at the main power disconnect switch.

3. Remove the burned-out compressor and install the new compressor.

4. Install a suction line filter-drier designed for acid removal.

5. Remove the liquid line drier and install an oversized liquid line filter-drier (one size larger than the normal selection size).

6. Check the expansion valve, sight glass, and other controls to see if cleaning or replacement is required.

7. Evacuate the system according to standard procedures. Normally this will include the use of a high-vacuum pump and a

low-vacuum micron gauge for measuring the vacuum obtained.

8. Recharge the system through the access valve on the suction line filter-drier.

9. Turn on power at the main power disconnect switch and start the system.

10. A permanently installed suction line filter-drier permits small-system cleanup to be completed in one service call. The pressure

drop across the suction line filter-drier should be measured during the first hour of operation. If the pressure drop becomes
excessive, the suction line filter-drier should be replaced (See Sporlan Bulletin 40-10, for the maximum recommended pressure
drop [PSI] for the suction line filter drier).

11. In 24 hours, take an oil sample. Observe the color and test for acidity. If the oil is dirty or acidic, replace the suction line

filter-drier.

12. In two weeks, examine oil to determine if another suction line filter-drier change is necessary.

5.3.4 Component Replacement

Check all electrical connections to ensure they are tight and properly made. Check all circuit breakers, contactors, and wiring. The
contactors should be examined and replaced if contacts are worn or pitted.

1. Turn off power to the unit at the main power disconnect switch.

2. Remove the old component and install the new one.

3. Turn on power at the main power disconnect switch and start the system.

5.3.4.1 Fan Replacement

The EC Fans are located behind the front access panel. The panel must be removed to access the fans. The fans are equipped
with quick connect fittings for the power and control cables to make swap-out easy. Lift the retaining latch on top of the power
and control cable connector housings to unplug the cables. Cut the wire-ties holding the cable bundle in the cabinet.

Remove the four hex-bolts holding the inlet ring then remove the four hex-bolts holding the fan mounting bracket. Remove the
fan assembly together with the inlet ring from the cabinet. Remove the mounting bracket from the old fan and install it on the
new fan. Bolt the new fan assembly (together with the inlet ring) into the cabinet and plug the power and control cables into the
connectors.