Mv 12-21-32-50 Air/Water Cooled - Scotsman MV 12 Service Manual

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CAUTION: If the factory seal is broken on
the replacement drier, exposing it to the
atmosphere more than a few minutes, the
drier will absorb moisture from the
atmosphere and lose substantial ability
for moisture removal.
1. Remove the factory seals from the
replacement drier and install the drier in the
refrigerant lines with the arrow positioned in
the direction of the refrigerant flow.
2. Solder the drier into the lines, two places,
taking precautions to NOT OVERHEAT the
drier body, during installation soldering.
3. Purge the system and check for leaks.
4. Throughly evacuate the system to remove
moisture and non-condensables.
5. Charge the system with refrigerant, by weight.
SEE NAMEPLATE.
6. Replace and attach front and left side panel.
NOTE: Always install a replacement drier,
anytime the sealed refrigeration system is
opened. Do not replace the drier until all
other repair or replacement has been
completed.
REMOVAL AND REPLACEMENT OF THE
EVAPORATOR PLATE ASSEMBLY
1. Remove front and top panels.
2. Store refrigerant charge in liquid receiver and
isolate parts to be opened from the rest of the
systems.
3. Disconnect water distributor tube above the
evaporator plate and remove it.
4. Unsnap and remove evaporator cover
deflector.
5. Unloose and remove all screws securing the
evaporator frame to the chassis.
6. Unsolder and remove the refrigerant lines at
the top of the evaporator plate to be replaced.
7. Remove nuts at top and left and right side of
the evaporator to remove top and side trimming
that make the frame of the evaporator plate.
The evaporator plate is now free.
To replace the evaporator plate, reverse the
removal procedures. See nameplate. Weight in
proper charge of R 404 A in liquid phase.
WATER REGULATING VALVE
(WATER COOLED)
1. Shut off water.
2. Remove front and right side panel.
3. Unscrew water inlet fitting connection at the
water regulator valve to condenser bracket.
4. Purge system of refrigerant.
5. Unscrew fitting connection at outlet of valve.
6. Unsweat valve connection from "T" joint on
system liquid line.
7. Remove valve from machine.
Reverse to reassemble.
THERMOSTATIC EXPANSION VALVE
1. Remove front and top and right side panels.
2. Purge system of refrigerant.
3. Unsweat valve at inlet, equalizer, and outlet.
4. Remove insulation from valve bulb, remove
mouting straps and valve from cabinet.
5. Place new valve bulb in same place as old
valve, secure with straps, and reinsulate.
Reverse to reassemble.
NOTE: Always install a replacement drier,
anytime the sealed refrigeration system is
opened. Do not replace the drier until all
other repair or replacement has been
completed.
Throughly evacuate the system to remove
moisture and non-condensables.
FAN MOTOR OR BLADE
(LEFT AND RIGHT SIDE)
1. Remove top and left or right side service
panels.
2. Remove screws and fan motor shroud.
3. Unplug fan motor to be removed.
4. Remove fan motor bracket from upper tie rod
of unit chassis.
5. Remove fan blade from motor. Note location
on motor shaft, and hub position.
6. To replace fan motor also, remove it from
bracket.
Reverse to reassemble.
NOTE: When replacing a refrigeration
component, the exact refrigerant charge must
be weighed or metered into a completely
evacuated system, because the MV is a
critically charged system.
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