Hoshizaki HNC-120BE-L-BH, Руководство по обслуживанию

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A. Refrigeration Circuit Service Information (R600a)
WARNING
• Repairs requiring the refrigeration circuit to be opened must be performed by properly
trained service personnel.
• 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 1 MPa. Do not use R600a as a mixture with pressurized air for leak
testing.
NOTICE
• Do not leave the system open for longer than 15 minutes when replacing or servicing
parts. The Polyol Ester (POE) oils used in R600a appliances can absorb moisture
quickly. Therefore it is important to prevent moisture from entering the system when
replacing or servicing parts.
• 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. Install
the new drier with the arrow on the drier in the direction of the refrigerant flow.
• When brazing, protect the drier by using a wet cloth to prevent the drier from overheating.
Do not allow the drier to exceed 121°C.
Refrigerant leaks must be repaired as soon as they are discovered. If not, refrigerant charge
should be recovered from the system until the leak can be repaired. When repairing a leak:
• Repair the leak properly – Remove the refrigerant, examine the leak source, determine the
reason for the leak, and carry out the proper course of action.
• Before repairing the leak, ensure that the refrigerant has been recovered and the system
purged with nitrogen when brazing.
• Be sure to remove piercing valves attached to the system after repairs are made.
1. Refrigerant Recovery
Using proper refrigerant practices, place piercing valves toward the end (crimped area) of
the high and low-side process tubes, then recover the refrigerant into an approved container
or device.