Hoshizaki DCM-500BWH-OS service manual G. Removal and Replacement of Water Regulating Valve ‑

Models: DCM-500BWH-OS

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G. Removal and Replacement of Water Regulating Valve ‑

G. Removal and Replacement of Water Regulating Valve

WaterCooled Model Only

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.

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 left side panel.

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

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

5)Close the condenser water supply line shut-off valve, then open the condenser water supply line drain valve.

6)Attach a compressed air or carbon dioxide supply to the condenser water supply line drain valve.

7)Open the water regulating valve by using a screwdriver to pry up on the spring retainer underneath the spring. While holding the valve open, blow out the condenser using the compressed air or carbon dioxide supply until water stops coming out.

8)Disconnect the capillary tube at the condenser outlet.

9)Disconnect the flare-connections of the valve.

10)Remove the screws and the valve from the bracket.

11)Install the new valve.

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

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 flare-connections.

17)Close the condenser water supply line drain valve, then open the condenser water supply line shut-off valve.

18)Check for water leaks.

19)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.

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Page 58
Image 58
Hoshizaki DCM-500BWH-OS service manual G. Removal and Replacement of Water Regulating Valve ‑, Water‑Cooled Model Only