4.Troubleshooting and System Detailed Diagnosis For ADC Direct Spark Ignition (DSI) Module P/N 128973

When the dryer calls for heat, 24 VAC from the step down transformer is applied to the “TH” and “GND” terminals of the DSI module. The DSI module light emitting diode (L.E.D.) indicator will LIGHT “RED” (for up to approximately 1.5-seconds [prepurge]) then the L.E.D. indicator will LIGHT “GREEN”; the gas valve will be energized, and the spark burst will be evident (on) for approximately 8-seconds at the tip of the electrode flame-probe assembly. The flame should now be established and confirmed. If a flame is not sensed and confirmed by the ignitor/flame-probe sensor after the approximate 8-seconds spark burst, the DSI module will go into the “LOCKOUT” mode and the L.E.D. will LIGHT “RED” CONTINUOUSLY. THERE ARE NO RETRIES. “Burner Ignition Control Fault” will display. To clear this fault press the “CLEAR/STOP” key.

If a flame has been established and confirmed and then lost, the DSI module L.E.D. indicator will continue to LIGHT “GREEN” and immediately a spark will be evident (on) for approximately 8-seconds. The flame should now be established and confirmed. If a flame is not sensed and confirmed by the ignitor/flame- probe sensor after the approximate 8-seconds spark burst, the DSI module will go into the “LOCKOUT” mode and the L.E.D. will LIGHT “RED” CONTINUOUSLY. THERE ARE NO RETRIES.

a. System Diagnosis

1) Gas Pressure

A gas pressure test should be taken at the gas valve pressure tap provided on every gas valve to assure that the water column (W.C.) pressure is correct and consistent.

There are two (2) types of devices commonly used to measure water column pressure. They are the spring and mechanical type gauges and the water column test gauge (manometers). The use of the spring and mechanical type gauges is not recommended because they are not always accurate. The preferred type of gauge is the manometer because it is a simple device to use and is highly accurate. A manometer is simply a glass or transparent plastic tube with a scale graduated in inches. When it is filled with water and pressure is applied, the water in the inner tube lowers, showing the exact water column pressure in inches.

WARNING: Test ALL connections for leaks by brushing on a soapy water solution.

WARNING: NEVER TEST FOR LEAKS

WITH A FLAME!!!

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American Dryer Corp AD-310 Phase 7 service manual With a Flame