AAON RQ NextGen Series, Установка, эксплуатация и обслуживание

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Table 20 - Chilled Water Coil Connection
Sizes
Model (RQ-)
Chilled Water Coil
Connection Size [mm (in.)]
002-006 29 (1 1/8)
Table 21 – Min and Max Water Pressures
and Temps
Packaged Direct Expansion (DX) Units
DX refrigeration system is factory
assembled, leak tested, charged with
refrigerant and run tested.
Refrigerant system includes an evaporator,
condenser, liquid line filter drier, thermal
expansion valve (TXV), and scroll
compressor. Variable speed compressor
systems include an electronic expansion
valve (EEV). Compressor is equipped with a
positive pressure forced lubrication system.
Never cut off the main power supply to the
unit, except for servicing, emergency, or
complete shutdown of the unit. When power
is cut off from the unit crankcase heater
cannot prevent refrigerant migration into the
compressor. This means the compressor will
cool down and liquid refrigerant may
accumulate in the compressor. The
compressor is designed to pump refrigerant
gas and damage may occur when power is
restored.
If power to the unit must be off for more than
an hour, turn the thermostat system switch to
"OFF", or turn the unit off at the control
panel, and leave the unit off until the main
power switch has been turned on again for at
least 24 hours for units with compressor
crankcase heaters. This will give the
crankcase heater time to clear any liquid
Chilled Water Hot Water
Min. Entering Air 15.6°C (60 ° F) 4.4 °C (40 ° F)
Max Entering Air
37.8°C (100
°
F) 26.7°C (80
°
F)
Min. Entering Water 1.7°C (35°F) 60°C (140°F)
Max Entering Water 18.3°C (65 °
F) 93.3°C (200
°
F)
Min. Water Pressure 0 kpa (15 psig)
Max Water Pressure 2068kpa (300 psig)
The unit shall have proper sealing of
the water piping entries into the unit.
Failure to seal the entries may result
in damage to the unit and property.
CAUTION
COMPRESSOR CYCLING
3 MINUTE MINIMUM OFF TIME
To prevent motor overheating
compressors must cycle off for a
minimum of 3 minutes.
5 MINUTE MINIMUM ON TIME
To maintain the proper oil level
compressors must cycle on for a
minimum of 5 minutes.
The cycle rate must not exceed 7
starts per hour.
WARNING
CRANKCASE HEATER
OPERATION
Some units are equipped with a
compressor crankcase heater, which
must be energized at least 24 hours
prior to cooling operation, to clear any
liquid refrigerant from the compressor.
CAUTION