Scotsman CME506R AutoIQ - Manual (Page 39)

Removal and Replacement:
Transformer and Compressor Starting
Components
Single phase compressors use a start relay, start
capacitor and run capacitor. All are located in a
sheet metal box to the right of the AutoIQ
Controller. The compressor contactor is also
located in that box.
1. Disconnect electrical power.
2. Remove front panel.
3. Remove 2 screws at the front edge of the metal
box, and pull the cover forward and out.
4. To check components, reconnect electrical
power.
Note: The contactor coil is 24 volt.
Refrigeration System Components
Due to the expected level of training and
experience of a refrigeration mechanic, detailed
instructions regarding the replacement of
refrigeration components will not be presented.
However, critical items will be noted here.
Evaporators
In the unlikely event that an evaporator may need
to be replaced, do NOT braze the evaporator joints
when the evaporators are seated in the freezing
compartment, instead lift them up slightly so that
the joints to be brazed are above the top edge of
the freezing compartment.
Refrigerant:
This ice machine uses R-404A or HP62 as a
refrigerant. It has several unique characteristics.
A. It must use polyol ester refrigerant oil, and that
oil is very water absorbent. The system must not
be open for more than 15 minutes.
B. An electronic leak detector capable of locating
HFC-134a type refrigerant must be used to locate
refrigerant leaks.
C. A nitrogen sweep is required when brazing.
D. An HFC type liquid line dryer must be used.
E. When evacuating, use of an electronic micron
gage is recommended. Evacuate to 300 microns.
F. It must be liquid charged:
1. Place a drum or cylinder of R-404A on a scale,
in the direction to dispense liquid.
2. Attach the charging hose to the cylinder of
R-404A. Open the cylinder’s valve and purge the
hose to the manifold.
3. Close the low side service access valve.
4. Open the discharge side manifold valve and
weigh in the name plate charge. After the charge is
weighed in, wait a moment and re-check the scale.
5. If all of the refrigerant charge has not been
weighed into the discharge side, it must be
carefully added thru the low side. Close the
discharge service access valve.
6. With a sight glass or charge faster in the hose to
the low side port, start the ice machine.
7. Open the low side service access valve.
8. Crack open the low side manifold valve and
watch the scale and sight glass. Open and close
the low side manifold valve to flow liquid into the
manifold but flash off to vapor before it enters the
suction side of the refrigeration system.
9. After the scale = the correct charge, shut off the
valve on the refrigerant cylinder.
CME506R, 656R, 806R: AutoIQ Cubers
January 2000
Page 39