American Dryer Corp. AD-540, Service Procedure

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35
2) Direct Spark Ignition (DSI) module light emitting diode (L.E.D.) indicator lights “GREEN” for up to
approximately 1.5-seconds (prepurge). This indicates that ALL the controls (including ALL the
safety circuits) are functioning and power is being supplied to the DSI module.
a) DSI module L.E.D. indicator lights “GREEN.” This indicates a normal heating cycle. This also
indicates that the preliminary diagnostics of the module has confirmed that the DSI module is
functional.
b) DSI module L.E.D. indicator lights a blinking “GREEN” light continuously...LOCKOUT mode.
This indicates that the module tried to ignite the gas a total of three (3) times of an 8-second
spark each time. After the third time, this blinking “GREEN” L.E.D. comes on.
If the dryer repeatedly has DSI module “LOCKOUT” failures, the cause may be due to high
voltage (HV) getting into the DSI module probe circuit.
(1) Check to insure that the red voltage wire (between the ignitor spark electrode and the DSI
module) is not wrapped around the sensor probe wire (the wire between the DSI module
FP terminal and the ignitor assembly flame-probe). If the wires are touching one another,
separate and secure in place
AWAY FROM ONE ANOTHER .
(2) Check to insure that the dryer is properly grounded and that the ground connections (GND)
to the DSI module are secure.
(3) If the problem persists, it is most likely to be in the external components (not the DSI module),
or wiring, or due to flame out...proceed as follows:
NOTE: Preliminary steps - DO NOT OMIT - to minimize the time required to troubleshoot this
system.
(a) Disconnect electric power to the dryer.
(b) Visually check DSI components for apparent damage.
(c) Check wiring for loose connection, nicks or cracking at the ceramic insulator, or shorting
of sensor to burner.
(d) Inspect the DSI ignitor/flame-probe assembly...
check electrode for visible cracking at ceramic insulator or shorting of sensor to burner
check to insure flame sensor rod is positioned over flame area
check for carbon deposits on flame sensor rod
check to insure that there is a 1/8” gap between the ground rod and the ignitor spark
electrode
b. After performing these inspections and making corrections, restore electric power to the dryer, start the
dryer and operate through one (1) complete cycle to insure ALL components are functioning properly.
If a no heat condition persists, the three (3) visual indicators, annotated as Item C on page 36 , will help
isolate equipment problems and lead you directly to the proper Quick Reference Troubleshooting
Flowcharts on page 37 , page 38 , and page 39 .