b)Burner Door Switch Replacement

1)Discontinue electrical service to the dryer.

2)Loosen the 1/4-20 x 3/4" hex head machine bolts as well as the 1/4-20 hex nut.

3)Remove the four (4) Phillips head screws securing the burner switch cover plate to the switch body.

4)Mark, identify, and remove the wires from the burner door switch for correct replacement.

5)Remove the cord grip from the switch body.

6)To install new burner door switch, reverse Step #5 thru Step #2.

7)Reestablish electrical service to the dryer.

7.Steam Heat System

The steam dryer uses six (6) steam coils to produce a heat input of 60 Bhp (boiler horsepower). The dryer utilizes three (3) separate dampers to direct air in the drying process or cool down process of a cycle.

The first damper is the cool down damper located on the top of the dryer, and is used to bring fresh, room temperature air into the tumbler (basket). When the dryer is in the cool down mode or has reached its set point temperature, the damper will be in the open position further reducing increases in tumbler (basket) temperature. When there is a call for heat, the damper closes, thereby requiring ALL of the air entering the tumbler (basket) to go through the steam coils.

An inlet air damper is located in the middle of the right hand section of the dryer. During a call for heat, this damper opens, which allows ambient air into the dryer, which then goes through the steam coils, heating the air. During cool down, or if the dryer has reached its set point temperature, the damper closes eliminating air from going through the steam coils.

The heat reclaimer is used to divert a portion of the exhausted air and run it through the steam coil, reheating the air. Depending on the stroke at which the heat reclaimer has been set, the amount of reclaimed air will vary. The heat reclaimer is only opened during a call for heat. Once the dryers' set point temperature is reached or during a cool down mode the heat reclaimer will be closed.

Heat Mode Air Flow - during a call for heat, solenoid S10 turns on and air first enters the dryer on the bottom

right side of the dryer. The air then passes through the open inlet air damper, then passes through the six (6) steam coils to heat the air. Next, the air enters the tumbler (basket) heating the load inside. The air then goes through the lint screen. Once the air is filtered by the lint screen it is forced out of the exhaust by the blower. A percentage of the air being exhausted gets reheated by the heat reclaimer to be used again. (Refer to the Drying Cycle illustration [top illustration] on page 66.)

Temperature Set Point/Cool Down Mode - during a cool down mode, solenoid S10 turns off and solenoid S9 turns on. In this mode, the air enters through the cool down damper on top of the dryer and enters the tumbler (basket). The air then passes through the lint basket and gets pushed out of the exhaust by the blower wheel. (Refer to the Cool Down Cycle illustration [bottom illustration] on page 66.)

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ADC AD-464 service manual