Hoshizaki IM-21 Service Manual page 31

See the diagram on the right for layout of the
Controller Board.
VR: Variable Resistor
No. 2 through No. 5 adjustable
K: Connector
IC: Integrated Circuit Chip
LED: Light Emitting Diode
Indicator Lamp
TF: Transformer
X: Relay
RESET: Reset Button
To check the operation of the
board, push the Reset Button only
during the freeze cycle.
Relay
X1 - Actuator Motor and Pump Motor
X2 - Hot Gas Valve and Fan Motor
X3 - Water Valve
X4 - Compressor
Control
VR2 - Defrost Control
VR3 - Backup Timer
VR5 - Cube Control
All the controls are factory-adjusted. Do not
change setting except when replacing the
board or if the setting has changed. Refer to
"[e] CONTROLS AND ADJUSTMENT."
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