Checking The Controller Board - Hoshizaki KM-320MAH Service Manual

e) Freeze Timer
Adjust to proper specification, or the unit may not operate correctly.
The freeze timer is factory adjusted and no adjustment is required. The setting
determines the maximum allowed freeze time to prevent possible freeze-up issues.
.
f) Bin Control
When the ambient temperature is below 45°F (7°C), the bin control thermostat
operates to stop 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 might
cause severe damage to the icemaker resulting in failure.
No adjustment is required under normal use, as the bin control is factory-adjusted.
Adjust it, if necessary, so that the icemaker stops automatically within 10 seconds after
ice contacts the bin control thermostat bulb.

5. Checking the Controller Board

a) Visually check the sequence with the icemaker operating.
b) Visually check the controller board by using the following procedure:
1) Adjust the defrost timer to minimum position.
Disconnect the thermistor from the controller board.
Connect a 1.5 to 3.5 kΩ resistor to connector K3 (pins #1 and #2), and energize the
unit.
After the 1 minute ± 5 second water supply cycle and the 2 minute ± 10 second defrost
cycle, the unit should start the freeze cycle.
2) After the above step 1), disconnect the float switch leads from the controller board
within the first 5 minutes of the freeze cycle. The unit should go into the defrost cycle
after the first 5 minutes ± 20 seconds of the freeze cycle.
CAUTION
Dip Switch Setting
No. 9 No. 10
OFF OFF
OFF ON
ON OFF
ON ON
CAUTION
19
Time
(minutes)
60
50
70
60