American Dryer Corp AD-200 service manual Ignitor and Flame-Probe Assembly

Models: AD-200

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a)Connect the water column test gauge (manometer) to the gas valve pressure tap (1/8" N.P.T.). Refer to the illustration on previous page (page 22).

b)Start the dryer ... with the burner on, the correct water column pressure (W.C.) reading in inches should be:

Natural Gas ..................................... 3.5 - 4 inches W.C. L.P. (liquid propane) Gas ................ 10.5 - 11 inches W.C.

When a gas dryer in first started (during initial time of installation and start-up), it has a tendency not to ignite on the first ignition attempt. This is due to the fact that the gas supply piping is filled with air, so it may take a few minutes for the air to be purged from the supply lines. During this purge period there may be insufficient gas pressure for ignition, which might cause the DSI module to go into the "LOCK-OUT" mode (the L.E.D. [light emitting diode] will LIGHT "RED" CONTINUOUSLY).

NOTE: During the purge period, check to be sure that ALL shut-off valves are open.

NOTE: To reset the DSI module if it is in the "LOCK-OUT" mode, open and close the main door, then restart the dryer.

c)If gas pressure is low, unscrew slotted regulator cover on top of the gas valve and turn regulator (pressure) adjustment screw (located underneath the cover) clockwise (CW) to increase the pressure.

2)Ignitor and Flame-Probe Assembly

The ignitor and flame-probe assembly consists of a ceramic insulated ignitor electrode, a ground rod, and a ceramic insulated flame-probe electrode. The GAP between the ignitor electrode and the ground rod is set, and must be maintained at 1/8" +/- 1/32" (.1250 +/- .03121).When the DSI module provides the high synchronous spark (14,000 volts) through the high voltage (HV) lead, a spark is produced over the GAP. When this spark is produced, the gas valve is opened. Upon ignition, the flame probe electrode (of the ignitor/flame-probe assembly) has high voltage provided to it that supplies a small current to ground through the flame. Once the current is sensed, it initializes the DSI module to sustain the gas flow (from the gas valve).

IMPORTANT: THE GAP SETTING ON THE IGNITOR/

FLAME-PROBE ASSEMBLY IS CRITICAL.

a) DSI Ignitor and Flame-Probe Assembly Adjustments

(1)The GAP on the ignitor and flame-probe

assembly must be set, and held at 1/8" +/- 1/32" (.1250 +/- .03121). If this GAP is not maintained (if the GAP is either to large or to small), the DSI module will indicate a system malfunction and go into the "LOCK-OUT" mode (the L.E.D. will

LIGHT "RED" CONTINUOUSLY).

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American Dryer Corp AD-200 service manual DSI Ignitor and Flame-Probe Assembly Adjustments