B. Removal and Replacement of Compressor

IMPORTANT

Always install a new drier every time the sealed refrigeration system is opened. Do not replace the drier until after all other repair or replacement has been made.

Note: When replacing a compressor with a defective winding, be sure to install the new start capacitor and start relay supplied with the replacement compressor. Due to the ability of the POE oil in the compressor to absorb moisture quickly, the compressor must not be opened more than 15 minutes for replacement or service. Do not mix lubricants of different compressors even if both are charged with R404A, except when they use the same lubricant.

1)Move the control switch to the "OFF" position, then turn off the power supply. Remove the front and top panels, then move the power switch to the "OFF" position.

2)Remove the apron panel, then remove the right side panel.

3)Disconnect the drip tray hose from the tee. Remove the four screws securing the drip tray, then remove the drip tray and hose.

4)Recover the refrigerant and store it in an approved container.

5)Remove the terminal cover on the compressor and disconnect the compressor wiring.

6)Remove the discharge, suction, and process pipes.

7)Remove the compressor hold-down bolts, washers, and rubber grommets.

8)Remove the compressor. Unpack the new compressor package.

9)Attach the rubber grommets of the prior compressor to the new compressor.

10)Place the compressor in position and secure it using the bolts and washers.

11)Remove the drier, then place the new drier in position.

12)Remove plugs from the suction, discharge, and process pipes.

13)Braze all fittings while purging with nitrogen gas flowing at a pressure of 3 to 4 PSIG.

14)Use an electronic leak detector or soap bubbles to check for leaks. Add a trace of refrigerant to the system (if using an electronic leak detector), and then raise the pressure using nitrogen gas (140 PSIG). DO NOT use R-404A as a mixture with pressurized air for leak testing.

15)Evacuate the system, and charge it with refrigerant. See the nameplate for the required refrigerant charge.

16)Connect the terminals and replace the terminal cover in its correct position.

17)Replace the drip tray and drip tray hose in their correct positions. Secure the hose to the tee. Pour water into the drip tray and check for leaks.

18)Move the power switch to the "ON" position, then replace the panels in their correct positions.

19)Turn on the power supply, then move the control switch to the "ICE" position to start the automatic icemaking process.

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Hoshizaki DCM-750BAH-OS, DCM-750BWH-OS service manual Removal and Replacement of Compressor