Aircel AES Series, Руководство пользователя

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VF, DHT, AES Series Manual |
Refrigerated Air Dryer User Manual
13
8. Ensure that the air system has come up to full pressure and
has filled the dryer with compressed air. Before opening
the outlet valve on the system and after the dryer has been
started under no load, let the dryer run for at least fifteen
(15) minutes to allow stabilization of the system. Verify the
following:
a. The dryer is designed to run continually and should
not be cycling on and off with the air compressor. The
non-cycling operation of the dryer is controlled by an
automatic expansion valve or a thermostatic expansion
valve / hot gas by-pass valve. The valves will open and
close automatically depending on the of heat load to
the evaporator, thus maintaining the desired pressure
dew point.
b. Check the inlet compressed air temperature and
pressure to the dryer and verify that it meets the
specified requirements.
c. Fan rotation, for dryers with an air-cooled condenser,
rotation should be in accordance with the fan rotation
shown on the details located on top and back of the
condenser. Cooling air is drawn through the condenser
coils. Three phase units are equipped with three phase
monitors, which will prevent the fan(s) and compressor
from running backwards. The unit will not turn on
unless the wire leads are in the correct location. The
phase monitor, located in the electrical box, will display
a green light, when the unit is phased properly. A red
light indicates that the unit is not phased properly. If the
motor rotation is not correct, turn off the power switch
and put the main power supply disconnect in the “off”
position; lock and tag; check the wiring; correct the wire
lead locations; recheck for correct phasing.
d. The refrigeration gauge readings should be as follows:
• Refrigerant suction pressure
R-134a = 28-40 psig
R-404a = 75-90 psig
• Refrigerant discharge pressure
R-134a = 160-230 psig
R-404a = 290-400 psig
9. After the preliminary start up checklist has been completed,
the compressed air outlet valve on the dryer system can
now be slowly opened to supply clean dry compressed air
to the facility.
10. After start-up and approximately one month of service,
check that all piping and fittings are tight and free of leaks.
3.6 Automatic Drain Valve Adjustments
The automatic drain valve supplied is standard on the separator
and should open regularly and discharge any accumulated
water into the drain line. The period between openings varies
with the dryer and operating conditions (electronic type). To
minimize air losses, the timer should be adjusted to open the
drain solenoid just long enough to discharge the accumulated
condensate. The factory sets the automatic drains to open for
7 seconds about every 7 minutes. If more than two seconds
of dry air comes out at the end of every discharge cycle,
reduce the open time (seconds) or increase the interval of the
discharge (minutes) to minimize air loss. If liquid is still being
discharged when the discharge cycle stops, increase the open
time (seconds) or shorten the interval of discharges (minutes)
so it discharges more often.
3.7 Zero Loss Condensate Drain
Aircel AES dryers are supplied with zero air loss condensate
drains standard on the separator and after the evaporator.
These drains should be checked regularly via the test
function to verify proper operation. The period between
openings varies with the operating conditions of the dryer.
The capacitive level sensing technology allows a direct acting
valve to discharge condensate without losing compressed air.
Unlike timer drains, these drains do not need to be adjusted.
The drain is equipped with an alarm feature. The alarm will
activate if the valve opens too many consecutive times without
a pause. If the alarm is activated check to see if debris is
blocking the valve or outlet.
NOTICE
The above discharge pressure depend upon ambient
temperature and can vary slightly according to
temperature fluctuations.
NOTICE
• Models with the hot gas by-pass valves and
expansion valves are preset at the factory for
the desired dew point. Do not adjust without
consulting with the factory.*
• The dryers are fully automatic and do not require
any auxiliary controls.
* Adjustments not authorized by the factory may void the
warranty.