American Dryer Corp ADG-530 technical manual Troubleshooting, Normal Operation summary

3.NORMAL OPERATION (summary)

When a signal is received from the thermostat supplying 24 volts to the W terminal of the HSI module, the control will reset, perform a self check routine, flash the diagnostic L.E.D. for up to four (4) seconds and a pre-purge delay begins. Following the inter-purge period, the Hot Surface Ignitor is activated and the Gas Valve is energized for the trial for ignition period. When a flame is detected during the trial for ignition, the Hot Surface Ignitor is deactivated and the Gas Valve remains energized. The thermostat and main burner flame are constantly monitored to assure the system continues to operate properly. When the thermostat/micro processor controller (computer) is satisfied and the demand for heat ends, the Gas Valve is de-energized immediately.

Should the main burner fail to light, or a flame is not detected during the first trial for ignition period, the Gas Valve is de-energized and the HSI Module (controller) goes through an inter-purge delay before another ignition cycle is attempted. The HSI Module will attempt two (2) additional ignition trials before going into LOCKOUT and the Gas Valve relay will be de-energized immediately.

Recovery from LOCKOUT requires a manual reset by either resetting the thermostat or removing the 24 volts for a period of five (5) seconds.

If the computer is still calling for heat after one (1) hour the HSI Module (controller) will automatically reset and attempt to ignite the burner again.

D. TROUBLESHOOTING

The troubleshooting information provided in this manual is intended for use only by QUALIFIED SERVICE TECHNICIANS. Observe ALL safety precautions displayed on the equipment or specified in the Installation/Operator’s Manual included with the dryer.

IMPORTANT: UNDER NO CIRCUMSTANCES SHOULD ANY SAFETY OR HEAT CIRCUIT DEVICE EVER BE DISABLED.

The following troubleshooting guide provides systematic procedures for isolating equipment problems, and again, is intended for use by a QUALIFIED SERVICE TECHNICIAN.

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