Service manual

Ice Maker
4-2
Water Valve Assembly
The water valve is solenoid operated, and when
energized, releases water from the household supply into
the ice mold. The amount of water released is directly
proportional to the length of time the water valve switch
is energized. A fl ow washer inside the water valve,
maintains a constant rate of water fl ow over a supply
line with pressure ranging from 20 to 100 psig. It will not
compensate for pressures below 20 psig, or greater than
100 psig. A No. 80-mesh screen, placed ahead of the
fl ow washer, fi lters out foreign materials.
The solenoid coil draws 10 to 20 watts of power. The coil
is wired in series with the mold heater, across the supply
voltage.
Thermostat
The thermostat is a single-pole, single throw (SPST),
bimetallic, disk-type, thermal switch. It automatically
starts the harvest cycle when the ice is frozen. The
thermostat closes at a temperature of 9°F ± 2°. Wired
in series with the mold heater, the thermostat acts as
a safety device against overheating in the event of
mechanical failure. A thermalmastic bond is provided
where the thermostat is mounted against the mold. A
gasket prevents water from leaking into the support
housing.
Sensing Arm & Linkage
The sensing arm is cam-driven and operates a switch
that controls the quantity of ice produced. In the harvest
cycle, the arm is raised and lowered during each of the
two revolutions of the timing cam. If the sensing arm
comes to rest on top of ice in the storage compartment
during either revolution, the switch will remain open and
stop the ice maker at the end of that revolution. When
suffi cient ice is removed from the storage container,
the sensing arm lowers and ice production resumes.
To manually stop the ice maker turn the switch located
on the housing at the left end of the ice maker to Off.
Operation is resumed when switch is turned back to On.
Ice Maker Components
Front Cover
A decorative molded plastic front cover encloses the
operating mechanism of the ice maker that protects the
mechanism from moisture. It is essential that the cover
be in place on an operating ice maker to protect against
possible contact with the mechanism by the user.
Ice Mold
The ice mold is die-cast aluminum with the ice maker
thermostat bonded to its front surface. The mold has
a semi-circular interior partitioned into equal size
compartments. Water enters at the side of the mold,
through a fi ll trough. A fi lm of silicon grease on the top
edge of the mold prevents siphoning of water by capillary
action.
Mold Heater
A mold heater, rated at 112 watts at 115 volts, 108
ohms ± 10%, is covered with an aluminum sheath and
embedded in the grooved section on the underside of
the ice mold. When the mold heater is energized, the ice
contact surface within the mold is heated enough to allow
harvest of the ice pieces.
The mold heater is wired in series with the ice maker
thermostat, which acts as a safety device.
The heater is staked in place, and is replaced as part of
the ice maker mold. A thermalmastic sealer is placed
between the heater and the mold to ensure good thermal
contact.
Ice Stripper
An ice stripper is attached to the mold to prevent ice
pieces from falling back into the mold. It also serves as a
decorative side cover.
Ice Ejector
The ejector blades are molded from delrin, and extend
from a central shaft, which turns in nylon bearings at the
front and rear. Each blade sweeps an ice section out of
the mold. The drive end of the ice ejector is “D” shaped.
Food grade silicone grease is used to lubricate the
bearing surfaces.