To avoid risk of electrical shock, personal injury, or death, disconnect electrical power source to unit, unless test
procedures require power to be connected. Discharge capacitor through a resistor before attempting to service.
Ensure all ground wires are connected before certifying unit as repaired and/or operational.
WARNING
!
When closed, it sends power to the common
terminal of the K6 relay (direction) and is an
SPDT relay.
The output from K5 is connected to the C
(common) terminal of K6. When it is not
energized (as shown above), power flows
through the C terminal, to the N.C. (normally
closed) contact and out the FWD contact on
the board.
K7 is the speed relay. It is an SPDT relay.
When not energized, the LO circuit is
energized through C terminal of the K7 relay.
This will cause both capacitors to be in series
causing the fan to run at a reduced speed.
The photo below shows the K7 energized.
The N.O. (normally open) terminal is now
closed causing a bypass of one of the two
capacitors. With only one capacitor in series,
the unit will run at a higher speed.
Clockwise (FWD)–High Speed
The photo below shows the K6 relay
energized which will cause the motor to rotate
in a REV (counterclockwise) direction. K7 is
not closed, so the speed is LOW.
Counterclockwise (REV)–Low Speed
The photo below shows the K6 (direction)
and K7 (speed) relays energized. This
will cause the motor to rotate in a REV
(counterclockwise) direction and at a higher
speed.
Counterclockwise (REV)–High Speed
Troubleshooting
©2012 Viking Preferred Service
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