American Dryer Corp. AD-200 PHASE 7 Clothes Dryer User Manual


 
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1. Steam Coil PH Level
The normal PH level for copper type steam coils must be maintained between a value of 8.5 to 9.5. For
steel type steam coils the PH level must be maintained between a value of 9.5 to 10.5. These limits are set
to limit the acid attack of the steam coils.
IMPORTANT: Coil failure due to improper PH level will VOID THE WARRANTY.
2. Steam Damper Actuator System
The steam damper actuator system consists of a hinged damper plate, pneumatic piston, and a 24 volt
solenoid valve with a needle valve to control the speed of the piston actuation.
On a call for heat, a 24 volt signal is applied to the 3-way/2-position solenoid valve. This signal switches the
valve so that compressed air is sent to the piston. The piston rod extends, pushing the hinged steam damper
plate to the open position. This allows room air to be drawn through the hot steam coil and then through the
tumbler (basket).
When the temperature set point has been reached, the 24 volt signal is removed from the solenoid valve, so
that the solenoid valve blocks the air supply to the piston, and air in the piston is bled to the atmosphere. The
spring in the piston now retracts the piston rod, closing the steam damper. The steam damper plate now
covers the steam coil and allows room air to bypass the coil before entering the tumbler (basket) for a rapid
cool down.