Refrigeration Circuit Service Information; Refrigerant Recovery - Hoshizaki Steelheart Series Service Manual

A. Refrigeration Circuit Service Information
• Repairs requiring the refrigeration circuit to be opened must be performed by
properly trained and EPA-certified 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 (190 PSIG). Do not use R-290 as a mixture with
pressurized air for leak testing.
• Always recover the refrigerant and store it in an approved container. Do not
discharge the refrigerant into the atmosphere.
• Do not leave the system open for longer than 15 min. when replacing or servicing
parts. The Polyol Ester (POE) oils used in R-290 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 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 250°F (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.
WARNING
NOTICE
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