Hoshizaki REFRIGERATED PREP TABLE WITH RAISED RAIL 73168 - Manual (Page 39)

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IV. Removal and Replacement of Components
WARNING
1. This unit should be diagnosed and repaired only by qualified service
personnel to reduce the risk of death, electric shock, serious injury, or fire.
2. Move the power switch to the "OFF" position and unplug the unit before
servicing.
3. Make sure all food zones are clean after the unit is serviced. For cleaning
procedures, see "V. Cleaning and Maintenance Instructions."
A. Service for Refrigerant Lines
WARNING
1. Repairs requiring the refrigeration circuit to be opened must be performed by
properly trained and EPA-certified service personnel.
2. Always recover the refrigerant and store it in an approved container. Do not
discharge the refrigerant into the atmosphere.
3. 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.
CAUTION
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.
3. 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.
4. 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).
5. Do not leave the system open for longer than 15 minutes when replacing or
servicing parts.
1. Refrigerant Recovery
The unit is provided with a receiver service valve, and compressor and rail access
valves. Using proper refrigerant practices, recover the refrigerant from the receiver
service valve and compressor access valve and store it in an approved container. Do not
discharge the refrigerant into the atmosphere.
Note: Attach the high-side gauge manifold hose to the receiver service valve before
opening the receiver service valve.