Sequence Of Operation; Sequence Cycles And Shutdown; A) 1-Minute Fill Cycle; B) Initial Harvest Cycle - Hoshizaki KM-1301SAH/3 Service Manual

B. Sequence of Operation
This unit utilizes a thermostatic bin control. For operation, the K4 jumper
(4A4883G01) must be in place on the control board RED K4 connector.

1. Sequence Cycles and Shutdown

The steps in the sequence are as outlined below. When power is supplied, CB red
"POWER OK" LED and green "BC CLOSED" LED come on. The green "BC CLOSED"
LED is on continuously when the K4 jumper is in place. If CB yellow "BC OPEN" LED is
on, check that CB has the K4 jumper in place on CB RED K4 connector. This unit will not
operate unless the K4 jumper is in place. There is a 5-second delay before startup. Note
that the order of the component LEDs from the outer edge of CB is 1, 4, 3, 2.

a) 1-Minute Fill Cycle

LED 4 is on. WV and X2 relay (auxiliary code T-0 and U-0), X11 relay (auxiliary code
U-1 and later) energize and the 1-minute fill cycle begins. After 1 minute, CB checks for
a closed F/S. If F/S is closed, the harvest cycle begins. If not, WV remains energized
through additional 1-minute fill cycles until water fills the tank and closes F/S. This
serves as a low water safety to protect PM.

b) Initial Harvest Cycle

LEDs 1, 4, and 2 are on. WV and X2 relay (auxiliary code T-0, U-0), X11 relay (auxiliary
code U-1 and later) remain energized, HGV, X1 relay (auxiliary code T-0, U-0),
X10 relay (auxiliary code U-1 and later), Comp, and FMR energize. CB monitors the
warming of the evaporator via the thermistor located on the suction line. When the
thermistor reaches 48°F (9°C), CB reads a 3.9 kΩ signal from the thermistor and turns
harvest termination over to the harvest timer (S4 dip switch 1 & 2). The harvest timer
has settings of 60, 90, 120, and 180 seconds. For details, see "II.C.3.b) Harvest Timer
(S4 dip switch 1 & 2)." WV is energized during harvest for a maximum of 6 minutes or
the length of harvest minus 0 or 50 seconds (harvest pump timer (S4 dip switch 7)),
whichever is shorter. CAUTION! Do not adjust S4 dip switch 7 out of the factory
default position on this model. Adjustment outside of the factory default position
may result in damage to the icemaker. For details, see "II.C.3.e) Harvest Pump Timer
(S4 dip switch 7)." LED 4 goes off when WV and X2 relay (auxiliary code T-0, U-0),
X11 relay (auxiliary code U-1 and later) de-energize. LED 3 comes on and PM energizes
and runs for the last 0 or 50 seconds of harvest depending on S4 dip switch 7 setting.
This circulates water over the evaporator for the last 0 or 50 seconds of harvest. PM
is energized through the #5 pin (DBu wire) on the CB K1 ten-pin connector and the
X1 relay (auxiliary code T-0, U-0), X10 relay (auxiliary code U-1 and later). When the
harvest timer expires, the harvest cycle is complete. CB checks the position of F/S and
proceeds to the freeze cycle if it is closed or calls for a 1-minute fill cycle if it is open. The
minimum total time allowed by CB for a complete harvest cycle is 2 minutes.

c) Freeze Cycle

LED 1 is on. Comp and FMR remain energized, PM energizes or remains energized
depending on harvest pump timer (S4 dip switch 7) setting. FM and LLV energize.
HGV and X1 relay (auxiliary code T-0, U-0), X10 relay (auxiliary code U-1 and later)
IMPORTANT
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