Start-Up - Scotsman MV 12 Service Manual

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START-UP

1. START-UP
1. If not yet done remove screws and pull the
Front Panel out.
2. Open the water supply line shut-off valve.
NOTE: Observe that the inlet water can be
seen flowing into the Sump Assembly.
Allow water to fill the Sump about three
minutes until the water is at level.
The float should cause the water flow to stop
few mm. from reservoir overflow.
When the float has been risen from the water
filling the Sump Assy, the water has forced all
trapped air out of Water Pump and pump tube,
thus preventing the pumping of water filled with
air bubbles.
3. Put unit under power by moving power line
switch to ON position.
Immediately the fourth "LED" will glow and four-
five seconds later the third one too together with
the compressor.
Check operation of the freezing cycle:
a) Compressor is operating.
b) Fan motor (in air cooled version) controlled
by the condensing temperature sensor located in
contact with the condenser copper tube.
c) Water pump is operating as seen by water
moving through the tygon tube up to the water
distributor at the top of evaporator plate, where
water is uniformly distributed and cascades down
over the egg-crate evaporator back into the Sump
for recirculation.
NOTE: The Water pump will start up after a
minute delay time controlled by the PC Board
so to avoid any possibility to such air
(cavitation).
NOTE: Do not remove the evaporator
deflector cover as it will cause the switching
off of the machine at "STORAGE BIN FULL".
4. First freezing time will range between 19
and 22 minutes.
Longer time for temperature above 25°C and
shorter time required when temperature are below
25°C.
Average complete cycle time is about 22 min.
5. Make sure of correct operation of float valve
and water pump.
6. Check for any irregular noise source and if
any, eliminate it.
7. Observe first ice cube harvest and check
size of ice cubes; if an adjustment is required
thread down or out screw N. 1 as shown on below
illustration.
This screw position determines the distance
between the sensor reeds and the egg-crate
evaporator thus keeping the ice cube at a proper
thickness.
NOTE: This type of machine produce an
"ICE PLATE" that breaks when falls down
into the storage bin. Setting the ice thickness
sensor in order to have single ice cubes
may cause malfunction of the machine.
8. Observe second and third cube harvest.
Check if size and shape combination is correct.
In areas where extreme problem water conditions
exist, filtering or purifyng equipment is
recommended.
NOTE: If water used is too soft,
"demineralized" the ice thickness sensor
might not be able to sense the water on its
reeds, there by it will not switch the unit on
harvest cycle.
A safety system built in the P.C. Board
switches the unit on harvest cycle whenever
the freezing period gets longer then 40'.
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