Hoshizaki KM-901MWH - Manual (Page 70)

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4) Close the low-side valve and high-side valve on the gauge manifold.
5) Disconnect the gauge manifold hose from the vacuum pump and attach it to a
refrigerant service cylinder. 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 rating label inside the
icemaker. Hoshizaki recommends only virgin refrigerant or reclaimed refrigerant which
meets ARI Standard 700 (latest edition) be used.
6) A liquid charge is recommended for charging an R-404A system. Invert the service
cylinder and place it on scales. Open the high-side valve on the gauge manifold.
7) Allow the system to charge with liquid until the proper charge weight is met.
8) If necessary, add any remaining charge to the system through the low-side. Use a
throttling valve or liquid dispensing device to add the remaining liquid charge through
the low-side access valve with the unit running.
9) Close the gauge manifold valves and disconnect the gauge manifold hoses.
10) Cap the access valves to prevent a possible leak.
B. Removal and Replacement of Compressor
CAUTION
1. Always install a new drier every time the sealed refrigeration system is
opened.
2. 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.
3. 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).
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 R-404A, except when they use the same lubricant.
1) Turn off the power supply.
2) Remove the panels.
3) Recover the refrigerant and store it in an approved container.
4) Remove the terminal cover on the compressor and disconnect the compressor wiring.
On remote air-cooled models, disconnect the crankcase heater.
5) Remove the discharge, suction, and process pipes.
6) Remove the hold-down bolts, washers, and rubber grommets.
7) Remove the compressor. Unpack the new compressor package.