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D. STEAM COIL SYSTEM OPERATION
General Overview
The dryers' steam coil is constantly charged thereby eliminating repeated expansion and contraction and also
provide instant heating to start the drying process. The steam damper, located on top of the steam coil, is the only
temperature controlling device in this system. When the steam damper is open, ambient air is drawn through the
coil providing heat to the dryer. When the steam damper is closed, ambient air is drawn directly into the tumbler,
bypassing the coil, allowing a rapid cool down.
NOTE: With the dryer off or no air supply to the damper piston, the damper is in the Cool Down mode...
the coil is constantly charged.
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.