York YK Style H Operation Manual page 46

Table 24: Display only fields
Field/LED name
Leaving Condenser Liquid
Temperature Setpoints – Effective
Offset
Leaving Condenser Liquid
Temperature Setpoints – Restart
Leaving Condenser Liquid
Temperature Setpoints – Offset
Note: For fields requiring access level of SERVICE. Service Technicians must refer to the
OptiView Control Center - Service Instructions (Form 160.76-M1) for operation instructions and
explanation of all programmable setpoints and displayed values.
Table 25: Programmable
Button Access level
Unit Control
Operator
Mode
Local Heating
Temperature – Operator
Setpoint
Leaving
Condenser Liquid
Temperature Operator
Cycling Offset –
Shutdown
Leaving
Condenser Liquid
Temperature Operator
Cycling Offset –
Restart
Heating LCHLT
Operator
Shutdown
46
Description
Displays the actual offset being used to create the Leaving Condenser Liquid
Temperature setpoints – Shutdown temperature above. See Leaving Condenser Liquid
Temperature Cycling Offset – Shutdown Setpoint description below.
Displays the Leaving Condenser Liquid Temperature at which the Heat Pump will
restart after shutting down on LEAVING CONDENSER LIQUID – HIGH TEM-PERATURE
cycling shutdown in Heating mode. See Leaving Condenser Liquid Temperature
Cycling Offset – Restart Setpoint description below.
Displays the offset being used to create the Leaving Condenser Liquid Temperature
Setpoints – Restart temperature above. See Leaving Condenser Liquid Temperature
Cycling Offset – Restart Setpoint description below.
Description
This setpoint can only be changed when the chiller is stopped. This setpoint sets the
Heat Pump operation to either Cooling (default), Heating, or Cooling and Heating
operation.
This allows the user to define the Local Mode Heat Pump Leaving Condenser Liquid
Temperature Setpoint that is to be maintained in Heating mode. It is programmable
over the range of 65.0°F to 122.0°F (default 95.0°F). A remote device can provide an
analog signal (4 mA to 20 mA, 0 VDC to 10 VDC, or a PWM) that changes the setpoint
as bounded by the Minimum and Maximum user range settings. An SC-EQ in BAS
Remote mode can set the setpoint through a serial communications interface.
This setpoint allows the user to specify the Leaving Condenser Liquid Temperature
at which the Heat Pump will shutdown on LEAVING CONDENSER LIQUID – HIGH
TEMPERATURE cycling shutdown in Heating mode. This is done by defining an
offset above the Leaving Condenser Liquid Temperature Setpoint. The offset is
programmable over the range of 1 to 59°F (default 1) above the setpoint, to a
maximum of 125°F. Anytime the Leaving Condenser Liquid Temperature Setpoint is
decreased, this shutdown threshold is ramped to the new setpoint at the rate of 0.1/s
to eliminate nuisance shutdowns.
This setpoint allows the user to specify the Leaving Condenser Liquid Temperature at
which the Heat Pump will restart after a shutdown on a LEAVING CONDENSER LIQUID
TEMPERATURE – HIGH TEMPERATURE cycling shutdown in Heating mode. This is done
by defining an offset below the Leaving Condenser Liquid Temperature Setpoint. It
is programmable over a range of 0 to 67°F (default 0) below the Leaving Condenser
Liquid Temperature Setpoint, to a minimum of 55°F. The chiller will automatically
restart when this temperature is reached. This setpoint can be used to reduce chiller
cycling by delaying the Heat Pump restart until the heating load has increased.
In Heating mode, the existing LEAVING CHILLED LIQUID TEMPERATURE – LOW
TEMPERATURE cycling shutdown logic includes an additional check to its existing logic
that causes a shutdown in Heating mode. This setpoint allows the user to specify the
Leaving Chilled Liquid Temperature at which the Heat Pump shuts down on LEAVING
CHILLED LIQUID – LOW TEMPERATURE cycling shutdown when the Heat Pump is
operating in Heating mode.
The low limit for this setpoint is the higher of (Leaving Condenser Liquid Temperature
Setpoint minus 71°F) or (Cooling mode Leaving Chilled Liquid Temperature Shutdown
Temperature). The high limit for this setpoint is the Leaving Condenser Liquid
Temperature Setpoint. The default is (Leaving Condenser Liquid Temperature Setpoint
minus 60°F).
The Heat Pump restarts when the Leaving Chilled Liquid Temperature exceeds this
shutdown temperature by 5°F.
Model YK Style H Centrifugal Liquid Chillers with OptiView Control Center