7JOHNSON CONTROLS
FORM 160.80-EG1 (808)
The EVAPORATOR screen displays a cutaway view of
the chiller evaporator. All setpoints relating to the evapo-
rator side of the chiller are maintained on this screen.
Animation of the evaporation process indicates whether
the chiller is presently in RUN condition (bubbling) and
liquid ow in the pipes is indicated by alternating shades
of color moving in and out of the pipes. Adjustable limits
on the low water temperature setpoints allow the chiller
to cycle on and off for greater efciency and less chiller
cycling. The chiller cycles off when the leaving chilled
water temperature is below setpoint and is adjustable
from 1°F (0.55°C) below to a minimum of 36°F (2.22°C).
Restart is adjustable from setpoint up to a max of 80°F
(44.4°C). The Panel will check for ow to avoid freeze-
up of the tubes. If ow is interrupted, shutdown will occur
after a minimum of two seconds. The following can also
be performed through this screen:
Display Only:
• Chilled Liquid Flow Switch (Open/Closed)
• Chilled Liquid Pump (Run/Stop)
• Evaporator Pressure
• Evaporator Saturation Temperature
• Return Chilled Liquid Temperature
• Leaving Chilled Liquid Temperature
• Evaporator Refrigerant Temperature
• Small Temperature Difference
• Leaving Chilled Liquid Temperature Setpoints –
Setpoint
• Leaving Chilled Liquid Temperature Setpoints –
Remote Range
• Leaving Chilled Liquid Temperature Setpoints –
Shutdown
• Leaving Chilled Liquid Temperature Setpoints –
Shutdown Offset
• Leaving Chilled Liquid Temperature Setpoints –
Restart
• Leaving Chilled Liquid Temperature Setpoints –
Restart Offset
• Ice Storage Active (LED)
Programmable:
• Local Leaving Chilled Liquid Temperature – Range
• Local Leaving Chilled Liquid Temperature – Setpoint
• Leaving Chilled Liquid Temperature Cycling Offset –
Shutdown
• Leaving Chilled Liquid Temperature Cycling Offset –
Restart
The CONDENSER screen displays a cutaway view of the
chiller condenser. The liquid ow is animated to indicate
ow through the condenser. All setpoints relating to the
condenser side of the chiller are maintained on this screen.
With the proper access level this screen also serves as a
gateway to controlling the Refrigerant Level. The following
can also be viewed through this screen:
Display Only:
• Leaving Condenser Liquid Temperature
• Return Condenser Liquid Temperature
• Condenser Pressure
• Condenser Saturation Temperature
• Small Temperature Difference
• High Pressure Switch (Open/Closed)
• Condenser Liquid Flow Switch
• Condenser Liquid Pump (Run/Stop)
Programmable:
• High Pressure Warning Threshold
• Freeze Warning (Enabled/Disabled)
• Freeze Time
The VARIABLE ORIFICE CONTROL screen, accessed
from the CONDENSER screen in SERVICE access level,
displays all of the applicable Variable Orice control
parameters and allows a Service Technician to program
the Delta P setpoint. The Low Evaporator Pressure and
Superheat Override LED’s are located on this screen.
A view of the liquid ow piping to the chiller condenser,
along with the solenoid ow control valve, is shown. The
following can also be performed through this screen:
Display Only:
• Condenser Pressure
• Evaporator Pressure
• Delta P (Condenser – Evaporator)
• Discharge Temperature
• Condenser Saturation Temperature
• Superheat Temperature
• Low Evaporator Override (LED)
• Superheat Override (LED)
Programmable:
• Delta P Setpoint