Water system
The water level in the evaporator is controlled by a fill solenoid
(Fig 1) and level detecting sensors. Water sensing
rods
(Fig. 2) extend down into the reservoir at the end of the evaporator assembly. The system works via electrical
conductivity as follows:
One of the longest probes is a common. When water is between any of the other probes and the common, the
PC board will sense the activation. During normal operation, the water level rises and falls between the Normal
High and Normal Low sensors. As water is consumed to make ice, the level will fall until the Normal Low sensor is
exposed, triggering the water feed solenoid on. Water will fill until the Normal High sensor is activated.
Note: The potable water dissolved solids content must be greater than 10 ppm for the water control system to
function properly. If using reverse osmosis water filtration system, ensure T.D.S level is greater than 10 ppm.
Fig. 1 Water system diagram
CLEANING CUP
WATER SUPPLY
3/8" FPT, 45-90 F (7-32 C)
10-70 PSI (69-483 KPA)
RESERVOIR FILL
SOLENOID
WASTE WATER DRAIN
3/4" FPT
WATER
RESERVOIR
EV
APORA
TOR
ICE
NOZZLE
DRAIN PAN
VENT
DRAIN
Fig. 2 Water level diagram
B
A
C
D
NORMAL OPERATING RANGE
A ALARM LOW (RED)
B COMMON (BLACK)
C NORMAL HIGH (ORANGE)
D NORMAL LOW (YELLOW)
B
A
B
A
C
D
C
D
10
MCD425A/W, R425A/W, MFD425A/W, P425A/W Ice Machines