Movincool Classic Plus 14, Service Manual

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ELECTRICAL SYSTEM
14
1. Basic Operation of Classic Plus 14
Electrical Circuit
There are two basic components used to control the operation of the Classic Plus 14 Electrical System:
• Control Panel Assembly
• Control Box
The Control Panel Assembly contains the Control Panel, Control Board (with inputs for the freeze
and room temperature thermistors), drain switch, and a microprocessor.
A. Fan “Only” Mode
Low Fan Mode - When the “Low” Fan Mode button on the control panel is pressed, the micropro-
cessor turns on the button’s LED and activates the Fan “On” Relay (Relay Board), sending line
voltage (115 VAC) to the N.C. (Normally Closed) contacts of the fan “mode” relay. This output is
connected to the J5 terminal (relay board) where the LOW SPEED wire of the fan motor is con-
nected.
High Fan Mode – When the “High” Fan Mode button on the control panel is pressed, the micropro-
cessor turns on the button’s LED and activates both the Fan “On” Relay and Fan “Mode” Relay.
This sends line voltage (115 VAC) from the Fan “On” Relay to the N.O. (Normally Open) contacts of
the Fan “Mode” Relay. This output is connected to the J6 terminal (Relay Board) where the HIGH
SPEED wire of the Fan Motor is connected.
B. Cool Mode - In Addition to Fan “Only” Mode (as described above)
When the Cool On/Off button on the control panel is pressed, the microprocessor turns on the
button’s LED and if the Temperature Set Point is less than the current room temperature, activates
the Compressor Relay (Relay Board). This sends line voltage (115 VAC) to the J4 terminal (Relay
Board) where the wire from pin 2 of the Compressor Overload Relay is connected. Pin 1 of the
Compressor Overload Relay is connected (by wire) to the compressor.