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Dryer controller diagram
Test fit the lid assembly on the jar.
Connect all the Tygon tubing and
plug all but one hose to test for system
pressure leaks by blowing into the
hose. The system must be completely
airtight. Fill the jar approximately half-full of desiccant and carefully insert
the lamp/tube into the desiccant.
Upon power up the unit will
circulate dry air through the engine
crankcase. At approximately 30
percent relative humidity, the
sensor will switch off the pump,
turn on the lamp, and open the
purge valve. The heated desiccant
then outgases its moisture. This
Purge valve control PC board and power supply mount on lid
can occasionally be observed as
a temporary condensation near
the top of the jar. With additional
heating, the humidity in the jar will
continue to rise and then start to
fall as the moisture is driven out of
the desiccant into the atmosphere.
When the humidity falls below 20
percent the lamp will shut off, the
purge valve closes, and the air pump
turns back on for the next engine
drying cycle. Typical purge time
will run one to two hours. This may
occur every couple of days in wet
environments.
Note: A thermal insulating blanket
surrounding the jar (not shown) will
greatly speed up the purge process.
In fact, it may be mandatory in cold
climates to get the temperature high
enough to drive out the moisture.
A full kit of parts with detailed
instructions is available for $95.
A partial kit, for those who built
the original one, is available; it
doesn’t include the air pump, Tygon
tubing, silica gel, Delrin cap, and
the brass air fitting for the oil cap.
The partial kit price is $80. For a
complete listing of materials needed
to build this engine dryer, visit www.
BarkerAircraft.com.
