V. removal and replacement of components, A. service for refrigerant lines, Refrigerant recovery – Hoshizaki MODULAR CRESCENT CUBER KM-650MWH User Manual
Page 39: Evacuation and recharge (r-404a)
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V. Removal and Replacement of Components
IMPORTANT
Ensure all components, fasteners and thumbscrews are securely in place after
the equipment is serviced.
IMPORTANT
1. The Polyol Ester (POE) oils used in R-404A units can absorb moisture
quickly. Therefore it is important to prevent moisture from entering the system
when replacing or servicing parts.
2. 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.
3. Do not leave the system open for longer than 15 minutes when replacing or
servicing parts.
A. Service for Refrigerant Lines
1. Refrigerant Recovery
The icemaker unit is provided with refrigerant access valves. Using proper refrigerant
practices recover the refrigerant from the access valves and store it in an approved
container. Do not discharge the refrigerant into the atmosphere.
2. Evacuation and Recharge (R-404A)
1) Attach service manifold hoses and a vacuum pump to the system. Be sure to connect
charging hoses to both high and low-side access valves.
IMPORTANT
The vacuum level and vacuum pump may be the same as those for current
refrigerants. However, the rubber hose and gauge manifold to be used for
evacuation and refrigerant charge should be exclusively for POE oils.
2) Turn on the vacuum pump. Never allow the oil in the vacuum pump to flow backward.
3) Allow the vacuum pump to pull down to a 29.9" Hg vacuum. Evacuating period depends
on pump capacity.
4) Close the low-side valve and high-side valve on the service manifold.
5) Disconnect the vacuum pump and attach a refrigerant service cylinder to the high-side
line. Remember to loosen the connection and purge the air from the hose.
For air-cooled and water-cooled models, see the nameplate for the required
refrigerant charge. For remote air-cooled models, see the charge label in the machine
compartment. Hoshizaki recommends only virgin refrigerant or reclaimed refrigerant
which meets ARI Standard No. 700-88 be used.