Service manual
AES Refrigerator GLOSSARY OF TERMS continued
MAIN SWITCH (1st Generation) - A rotary, two (2) position switch used to complete or interrupt
main power circuit to the printed circuit board. This switch utilizes an “OFF” and “ON” position
only. With switch turned “ON” the refrigerator will select and operate on the heat source available.
OFF-ON PROCEDURE
-
Any time the delay cycle is not desired it may be overridden by turning
the main switch to the “OFF” position, waiting approximately 5 seconds and then turning the
switch back “ON”. This procedure cancels the printed circuit board’s “memory” and refrigerator
will relight on LP gas within a few seconds.
POLARITY
-
The property of voltage that causes electrons to flow through a circuit in a certain
way. In a 12V DC circuit electrons flow from the negative connection on the battery, through the
interconnecting wiring and circuits, then back to the positive connection on the
12V
DC battery.
Because of this property, to insure proper operation of the refrigerator, the negative lead, from
the battery, must be connected to the negative connection on the refrigerator terminal block. The
positive lead from the battery must be connected to the positive connection on the terminal block.
PRINTED CIRCUIT BOARD
(PCB)
- Sometimes called a module board, this device controls many
of the operational sequences in the AES refrigerator. The board has three (3) primary functions
including:
A. Controlling all heat sources
(12OV,
12V
&
LP gas)
B. Monitors incoming battery voltage from terminal block
C. Controls the approximate 25 minute delay cycle from
12V
DC operation to LP gas operation.
RELAY. 12V DC
-
A component controlling the circuit to the 12V DC heating element. Containing
a set of normally open contacts, the relay will complete the circuit (by closing contacts) to the
heating element when proper voltage is established at the relay. With proper voltage supplied to
the relay, an internal coil is energized which closes the contacts to enable
12V
DC heating to
operate.
SWITCH BOARD (CARD) (2nd Generation) - Similar to the rotary switch found on 1st generation
AES models. The circuits are housed on a printed circuit “bread” board that includes a slide switch
and two (2) indicator L.E.D.‘s. Although appearance and diagnosis of this switch is slightly
different from the 1st generation switch, it functions the same in the electrical circuit.
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