13
B. Sequence of Operation
1. Sequence Cycles and Shutdown
The steps in the sequence are as outlined below. When power is supplied, the red
"POWER OK" LED and the green "BC CLOSED" LED on the CB turn on (If yellow
"BC OPEN" LED is on, the icemaker will not start. In this case clear ice away from BC
actuator paddle in the storage bin area). A 5-second delay occurs at startup. Note that
the order of the green sequence LEDs from the outer edge of the board is 1, 4, 3, 2.
a) 1-Minute Fill Cycle
LED 4 is on. WV1 opens and the ll period begins. After 1-minute, CB checks for closed
F/S. If F/S is closed, the harvest cycle begins. If not, WV1 will remain energized through
additional 1-minute cycles until water enters the water tank and F/S closes. This serves
as a low water safety to protect the water pump.
b) Initial Harvest Cycle
LEDs 1, 4 and 2 are on. Comp, FMRs, HGVs, X10 relay, WV2, X12 relay, and X13
relay energize. WV1 de-energizes. CBmonitors the warming of the evaporator via the
thermistor located on the suction line. When the thermistor reaches 48°F (9°C), CB
reads 3.9 kΩ from the thermistor and turns harvest termination over to the adjustable
harvest timer (S4 dip switch1 & 2). The harvest timer has settings of 60, 90, 120, and
180 seconds. The pump-out timer (S4 dip switch 3&4) acts in place of the harvest timer
during cycles with a pump-out (S4 dip switch 5&6). WV2 and X12 relay are energized
during harvest for a maximum of 6 minutes or the length of harvest minus 50 seconds,
whichever is shorter. 50seconds before the harvest timer terminates, harvest pump timer
starts. LED 4 turns off, WV2 and X12 relay de-energize.
Harvest Pump Timer: LEDs 1, 3, and 2 are on. Comp, FMRs, HGVs, X10 relay, and
X13 relay continue. LED 4 turns off, WV2 and X12 relay de-energize. LED 3 turns on and
X11 relay energizes, allowing PM to energize for the last 50 seconds of harvest. NOTICE!
S4 dip switch 7must remain in the factory default position of 7 on. Otherwise,
PM will not energize during the last 50 seconds of harvest. The minimum total
time allowed by CB for a complete harvest cycle is 2 minutes. At the end of harvest,
CB checks position of F/S and proceeds to the freeze cycle if it is closed or calls for a
1-minute ll if it is open.
c) Freeze Cycle
LED 1 and LED 4 are on. Comp, FMRs, and PM remain energized. LLVs energize. WV1
and LED 4 energize for 1 min. HGVs, X10, X11, and X13 relays de-energize. For the rst
5 minutes, CB will not terminate the freeze cycle. At the end of 5 minutes, F/S assumes
control of the freeze cycle. As ice builds on the evaporator, the water level in the water
tank lowers. Freeze continues until F/S opens, provided the 5-minute minimum freeze
timer has terminated.
