Grain Systems PNEG-1459 - Manual (Page 35)

35 PNEG-1459 L Series Operators
ADJUSTING DRYER AIRFLOW
CENTRIFUGAL DRY/VACUUM COOL DRYERS
The fresh air louvers, located on the sides of the fan-heater module, can be adjusted to balance the amount of cooling air
required. Opening the louvers wider will reduce the amount of vacuum cooling and increase the drying airflow rate. Closing
the louvers will increase the cooling airflow rate while reducing the amount of air to the drying zone.
In general, the louvers should be adjusted to create 2 to 2 1/2 inches of water column (wc) vacuum in the cooling plenum. The
louvers should be adjusted to approximately 8% open. With the Heat Reclaimer option, the louvers will be approximately 2%
open.
NOTE: As the louvers are adjusted, both drying and cooling capacities are affected. Higher static pressures will increase
cooling capacity, but decrease drying capacity. Lower static pressures will increase drying capacity but decrease cooling
capacity. Also, the unload rate can have an inpact on the louver settings. Lower unload rates can be operated at lower static
pressures since the grain is in the cooling section of the dryer for longer time periods.
When drying crops wetter than 25% moisture, dryer capacity may be improved by increasing the fresh air louver opening.
Monitor dry grain temperature for adequate cooling when making final adjustments.
The louvers can be adjusted by moving the HFWL 1/2-13 nuts located on the louver adjusting stud protruding through the dryer
floor panel on each side of the fan-heater module. Fine adjustments can be made by rotating the louver handle assembly. By
moving the louver handle assembly toward the center of the dryer, the HFWL nut will pass through the keyhole slot in the floor
panel allowing the louvers to be quickly moved to a closed position when not in use. When adjusting louvers, it is best to open
each side approximately the same.
When the dryer is shut off, the pressure guage (located on the right-hand side of the fan motor housing) should return to zero.
Over time, however, the gauge may drift out of calibration. If this occurs, rezero using the following process:
1. Unscrew the gauge cover by placing the palm of your hand over the lense and turning counterclockwise.
2. The zero adjust screw is located behind the scale (note the arrow in the photograph at the top of next page). Using a small
hex Allen wrench, adjust until the needle reads zero. Turning clockwise increases the reading, and counterclockwise decreases.
3. Reinstall the gauge cover.
Adjustment screw
DRYER OPERATION - ADVANCED MOISTURE CONTROL