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5. Push ESC button to exit program mode.
6. Manual Operation
a. To manually turn the refrigeration system on or off
use ‘On/Off’ button; Push ‘Schedule On/Off and
Enter’ button to return to schedule.
NOTE: After power interruption dryer will reenergize
in Manual override, refrigeration system off. To
restart Schedule: Push ‘Schedule On/Off and Enter’
button.
B.
Starting dryer
IMPORTANT: Dryer must be energized 24 hours before
starting refrigeration compressor.
NOTE: It is recommended that dryer be started 15 minutes
before compressed air flow begins.
1. On water-cooled models: after 24 hours, begin cooling
water flow.
2. Check for proper electrical voltage.
3. Slowly pressurize unit air side by opening inlet isolation
valve. Check for leaks.
4. After 15 minutes, open outlet isolation valve slowly.
5. Close air bypass valve.
6. Dryer may be operated in Manual or Scheduled modes.
NOTE: ON MODELS 500, 600, and 750, CHECK FOR CORRECT
PHASING OF UNIT. After starting the dryer, if an unusual
noise is heard, or if the discharge line does not get hot, the
refrigeration compressor may be running in the reverse
direction. Immediately stop the dryer, reverse two of the
power leads, restart the dryer, and verify the unusual noise is
corrected and the refrigerant discharge line is hot. FAILURE
TO DO SO MAY DAMAGE THE COMPRESSOR AND VOID THE
WARRANTY.
Manual
Mode - push On/Off button - refrigeration
compressor will start and run, green Compressor-on
light will illuminate. In this mode compressor will run
continuously and will not be turned on and off by the
monitor. MANUAL MODE will appear on interface panel.
Schedule
Mode - push Schedule On/Off and Enter button.
SCHEDULED MODE will appear on the interface panel.
The compressor will then turn on or off as programmed.
NOTE: Dryer may be returned to the Manual Mode at any
time using the ‘Schedule On/Off and Enter’ button or by
pressing On/Off button. MANUAL MODE will appear on
interface panel. To reinstitute Schedule, push the ‘Schedule
On/Off and Enter’ button again.
NOTE: Restart after the power interruption. Unit will be in
MANUAL MODE mode, refrigeration compressor, off when
power is restored after power interruption.
7. To reinstitute SCHEDULED MODE, push ‘Schedule On/
Off and Enter’ button.
IMPORTANT: Dryer must be energized 24 hours before
refrigeration compressor is started.
C.
Operating check points
1. Check that green Power-on light is illuminated
2. Check that green Compressor-on light is illuminated if
dryer is on in the manual mode or it is a scheduled on
time
IMPORTANT: Refrigeration compressor must be restarted
after power interruption.
3. Check interface panel
NOTE: Interface panel will scroll through three screens
(Current Time/Operating Status, Hours to Service and Total
Operating Hours).
a. Verify that current time is correct
b. Check HRS TO SERVICE: this indicates time remaining
until service is required; allow time for required
maintenance items to be ordered
c. Check operating status:
MANUAL MODE - Dryer is either running continuously
(not being controlled by the scheduled on/off times)
or the refrigeration compressor has been shut off
using the ‘On/Off’ button.
SCHEDULED MODE - Refrigeration compressor
is being turned on and off by the monitor per-
programmed schedule (see B.3. to set schedule).
d. Check Temperature indicator - indicator should read
in the green area.
e. Check Alarm/Service light If illuminated, check
Interface panel.
1) If SERVICE DRYER appears, scheduled maintenance
time has elapsed (HRS TO SERVICE is 0). Perform
needed service and reset service interval (see B.3.).
2) If ALARM appears, a dryer fault is indicated; see
Troubleshooting Guide for possible remedies.
After fault correction push Reset button to turn
Fault alarm off.
Type of FAULTS:
LOW PRESSURE - the refrigeration compressor
control circuit has opened because of low suction
pressure.
HIGH PRESSURE - the refrigeration compressor
control circuit has opened because of high head
pressure. The high pressure switch must be reset
manually once the fault is corrected. Red reset
button is located on pressure switch inside unit.
HIGH TEMPERATURE - compressed air temperature
is above the set point.
COMPRESSOR - Normally open (NO) auxiliary
contact on the compressor contactor is open
when the dryer is on.
HEATER - Normally closed (NC) auxiliary contact
on the compressor contactor is open when the
dryer is off.
TEMP SENSOR - Occurs if the temperature
sensor circuit is open or shorted. If open, none
of the LED’s in the temperature display will
be illuminated. If shorted, all the LEDs in the
temperature display will be illuminated.
DRAIN - electric drain contains a high water level
alarm that activates if drain fails to discharge.
f. Check drain operation - push Drain (push-to-
test) button to energize electric drain. A flow of
condensate and/or air should be present at the drain
outlet.