4 7D. STEAM COIL SYSTEM OPERATIONGeneral OverviewThe dryers' steam coil is constantly charged thereby eliminating repeated expansion and contraction and alsoprovide instant heating to start the drying process. The steam damper, located on top of the steam coil, is the onlytemperature controlling device in this system. When the steam damper is open, ambient air is drawn through thecoil 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 LevelThe 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. Theselimits are set to limit the acid attack of the steam coils.IMPORTANT: Coil failure due to improper PH level will VOID THE WARRANTY.