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#7040748 - Revision A - September, 2016
MODEL UW-24
MODEL UW-24
Electronic Control System
Supply Power to the Lighting System
AC line voltage is supplied to the door switch. The control board senses the position of the door switch and acti-
vates the lights accordingly. If the display lighting system is activated, the control boards ignores the position of the
door switch. If Sabbath Mode is activated the control board will not activate the light system.
ELECTRIC SHOCK HAZARD. 120 VOLTS AC IS STILL PRESENT AT THE CONTROL BOARD AND LIGHT
SWITCH WHEN LIGHTS ARE DISABLED.
FUNCTION OF THE ELECTRONIC CONTROL SYSTEM
The following pages explain monitoring, regulating and controlling functions of the electronic control system. Signal
traces from the UW-24 wiring schematic are used to show current flow for the functions being explained.
ELECTRIC SHOCK HAZARD! POWER TO THE UNIT MUST BE DISCONNECTED WHENEVER SERVICING
COMPONENTS POWERED BY ELECTRICITY OR COMPONENTS NEAR ELECTRICAL COMPONENTS. EVEN
WHEN SWITCHED OFF, AC LINE VOLTAGE IS STILL PRESENT AT THE CONTROL BOARD!
Display Average Compartment Temperatures
The temperature signals from the thermistor in each compartment is monitored by the microprocessor and shown in
the control panel LED display windows. The unit symbol next to the display window indicates which compartment
(upper or lower) the temperature is associated with. Though compartment air temperature fluctuates during normal
ON and OFF cycles of the cooling system, the “average”, or “product” temperature is shown in the LED display win-
dows (See Figure 2-15).
NOTES
:
•
The temperature range in a wine storage compartment is 40°F to 65°F.
•
If a compartment temperature should ever exceed either the high offset or low offset (for example: when a door is
left open), the temperature displayed at the control panel will change by no more than one degree per minute.
Figure 2-15. Temperature Display
Upper
Compartment
Temp Reading
Lower
Compartment
Temp Reading
Cabinet Upper Compartment Icon
Cabinet Lower Compartment Icon