York 160.87-OM1, Operation And Maintenance Manual

Page: 150 / 268

Table 144: Display only
Field/LED name Description
Leaving Chilled Liquid
Temperature
Displays the temperature of the liquid as it leaves the evaporator.
Leaving Chilled Active
Setpoint
Displays the setpoint to which the Leaving Chilled Liquid is being
controlled.
Quick Pulldown in Effect
(LED)
Illuminates while a Quick Pulldown is in effect. This is in effect from
a start initiate until the Quick Pulldown Setpoint Offset has been
reached or the Pulldown Override Time has elapsed, whichever
occurs first.
Note: For fields requiring access level of SERVICE. Qualified service technicians should refer
to the OptiView Control Center Service for operation instructions and explanations of all
programmable setpoints and displayed values.
Table 145: Programmable
Button Access level Description
Change
Setpoints
Service
Used to enter the following setpoints.
Pressing this key places a green selection box around the first
changeable setpoint. Use the ▲ and ▼ keys to place the selection
box around the desired setpoint. With the setpoint selected, press
the Enter key. A dialog box appears with the range of settings.
Mapping
Enable
Service
This is the same setpoint as shown on the ACC DETAILS Screen.
It can be programmed on either the ACC Screen or the QUICK
START Screen. It sets the Delta T needed to be met to enable surge
mapping and speed reduction initially on startup. (0.5°F to 4.0°F;
default 1.0°F)
Pulldown
Override
Time
Service
This setpoint is the length of time the PRV is held open (Quick
Restart) and the ACC speed (Quick Restart and Quick Normal Start)
is increased on startup if the Quick Pulldown Setpoint Offset is not
reached.
This could be due to hitting current limit during the pulldown. If
the Quick Pulldown Setpoint Offset is not reached in the Pulldown
Override Time, PRV and ACC speed control will revert back to normal
automatic control. (0 min to 15 min; default 10 min)
VSD Start
Frequency
Service
The VSD Start Frequency is as follows:
• 60 Hz units with quick start enabled equal 30 Hz to 45 Hz
(default 45 Hz)
• 50 Hz units equal 25 Hz to 37.5 Hz (default 37.5 Hz)
This setpoint is the same as shown on the ACC DETAILS Screen. It
can be programmed on either the ACC Screen or the QUICK START
Screen. It sets the VSD Start Frequency from which the speed will
ramp from.
YK-EP Style B Centrifugal Chiller 150