Bin Control; Thermostatic Bin Control: Auxiliary Code T-0, U-0; Mechanical Bin Control: Auxiliary Code U-1 And Later; Float Switch - Hoshizaki KM-901MAH Service Manual

D. Bin Control

1. Thermostatic Bin Control: Auxiliary Code T-0, U-0

When the ambient temperature is below 45°F (7°C), the thermostatic bin
control switch opens and shuts down the icemaker even if the ice storage bin
is empty. When the thermostat is set in the prohibited range, the icemaker
operates continuously even if the ice storage bin is filled with ice. Setting in the
prohibited range may result in severe damage to the icemaker.
The thermostatic bin control switch is a temperature controlled switch used to control
the level of ice in the bin. It is in line with the power supply to the control switch.
The thermostatic bin control switch shuts down the unit within 10 seconds when ice
contacts the thermostatic bulb, regardless of the cycle at activation. The thermostatic
bin control is factory set, and generally no adjustment is required. However,
adjustment may be needed in some conditions, particularly at higher altitude
locations. For further details, see "IV.C.1. Thermostatic Bin Control Check."

2. Mechanical Bin Control: Auxiliary Code U-1 and Later

The mechanical bin control is a lever-actuated bin control switch used to control the
level of ice in the bin. The mechanical bin control connects to the control board RED
K4 connector. When the actuator paddle is not engaged (mechanical bin control
switch closed; control board green "BC CLOSED" LED on), the unit produces ice.
When the actuator paddle is engaged (mechanical bin control switch open; control
board yellow "BC OPEN" LED on), the unit shuts down as outlined in the table below.
Cycle at
Mechanical Bin
Control Activation
Fill Cycle
Harvest Cycle
Freeze Cycle
E. Float Switch
The float switch is used to determine that there is sufficient water in the tank after
the 1-minute fill cycle and after each harvest cycle. The float switch is also used to
determine that the appropriate volume of water has been converted into ice before
switching out of the freeze cycle. No adjustment is required.
F. Thermistor
The thermistor is used as a harvest control sensor. The thermistor's resistance varies
depending on the suction line temperature. The control board monitors the resistance to
start the harvest timer. No adjustment is required.
G. Control Switch
The control switch has three positions: "OFF" for power off, "ICE" for icemaking, and
"WASH" to activate the water pump when cleaning and sanitizing.
CAUTION
Shutdown
15 seconds after activation.
At the end of the harvest cycle, or up to 15 seconds into the freeze cycle if
activated at the end of the harvest cycle.
15 seconds after activation if activated at least 15 seconds before the 5-minute
short cycle protection timer expires. Otherwise, at the end of the next harvest
cycle.
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