Sterling SDA 1000-5100 Large Dehumidifying Dryers, Troubleshooting, Problem, Possible Cause

Problem	Possible Cause	Corrective Action
Loss or reduction in	Process heaters are faulty.	Replace.
drying capacity.	Desiccant beds are contaminated.	Replace desiccant.
	Material being dried differs from	Drying systems are designed for
	material specified at the time of	the material that was originally
	purchase.	specified. Different materials may
		need a longer residence time or
		different drying temperature.
	Break in flex hose to/from drying	Inspect for air leaks; replace if
	hopper.	necessary.
	Blower fins filled with dust or	Remove blower side plate, clean
	contaminants.	baffles, replace. Replace filter
		elements.
Material in drying	Process temperature set too high	Check resin manufacturer's data
hopper cakes, or	due to operator error.	sheet for proper drying
meltdown occurs.		temperature. Make sure plant
		personnel are aware of the correct
		process temperature Set Point.
	High temperature alarm not set	See Section “Temperature Screen
	properly.	Setup” on page 29.
	Process set point is out of	Restore temperature controller to
	acceptable range.	factory pre-sets. Auto-tune if
		necessary.
Poor Dew Point	Burned out regeneration heater.	Repair or replace.
Performance.	Contaminated or worn out	Replace.
	desiccant.
	Leaking process air hoses.	Repair or replace.
	Dryer is being operated beyond its	Check dryer and drying hopper
	capacity.	sizing.
	Bad dew point sensor.	Replace.
	Fouled dew point sensor manifold.	Clear obstruction. Air should flow
		freely through sensor.

Large Dehumidifying Dryers Troubleshooting 50