Johnson Controls YEWS Series, Installation, Operation And Maintanance Instructions

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Compressor running hours and starting times.
Compressor running status.
System Suction/Discharge pressure, oil pressure, disch-
arge temerature.
Percentage of compressor current to Full Load Amps.
Cutout value and setpoints: Leaving Chilled (Hot) Water
Temperature, Low Evaporator Pressure , High Discharge
Temperature/Pressure , High/Low Amps , Low Chilled
Water Temperature , High Diacharge Pressure Unload,
High Compressor Amps unload.
Input
Setting the chilled (hot) water temperature.
Clock
Setting time, daily and holiday start/stop schedule.
Programming
Cutout setpoints: Low Evaporator pressure, High
Discharge Pressure, Low Evaporator temperature, High
Discharge Temperature, High Discharge pressure
unloading, OCC.
2.11 OPTIONS
YORK ISN building automation system can directly send
the communication signal to the standard control panel
through the standard RS485 connection.
Flow Switch
The gate type water flow switch has 10.3 bar DWP, which
is applicable to chilled water and cooling water lines.
25mm Spring Isolators
Level adjustable, spring and cage type isolators for
mounting under the unit base rails (Field mounted).
2.12 Functional Description
Low pressure liquid refrigerant enters the cooler and is
evaporated and superheated by the heat energy absorbed
from the chilled water passing through the cooler tube.
These low pressure vapor is sucked by the compressor
where the pressure and temperature are increased. The
high pressure and temperature refrigerant vapor combined
with oil is discharged into the oil separator, there, most of
the oil is separted and remaind in the oil reservoir. The oil
free vapor then enter the condenser and is condensed. The
fully condensed and subcooled liquid refrigerant then
enters the expansion valve where pressure reduction and
further cooling takes place before returning to the cooler.
YEWS-E Water Cooling Screw Chiller/Heat Pump