York 160.87-OM1, Operation And Maintenance Manual

Page: 40 / 268

Note: *The refrigerant level is animated in the cutaway view of the condenser. The actual level
of the refrigerant in the tank does not match the percentage displayed in the Level Control
Valve Command box. The actual levels versus the displayed percentages are:
Table 23: Condenser level position
Actual level
Control valve
command %
0% to 15% 50%
16% to 31% 60%
32% to 47% 70%
48% to 63% 80%
64% to 79% 90%
79% 100%
Table 24: Programmable
Button Access level Description
Level
Setpoint
Service
Displays the setpoint to which the refrigerant level is being
controlled. (Adjustable 20 to 80%; default 50%).
Startup
Position
Service
Sets the starting position of the refrigerant valve to allow the system
to match the load quicker. (Adjustable 0 to 100%; default 50%).
Startup Delay –
The amount of time the refrigerant level valve PID waits after start
before it starts controlling the valve position. This allows the system
to stabilize before making valve position changes. (Set at 15 seconds
but is adjustable with an Admin password).
Ramp Time Admin
After the chiller has been running for the level control startup delay
time, if the refrigerant level is less than the Level Setpoint, a linearly
increasing ramp is applied to the Level Setpoint. This ramp allows
the level to go from the present level to the programmed Level
Setpoint over a period of time programmed as the Ramp Up Time.
This setpoint can only be changed with ADMIN level access.(1 to 5
minutes; default 1).
Manual
Increment
Admin
This sets the percentage the refrigerant valve will manually be
driven with each press of the Open or Close buttons. (0.1 to 10%;
default 1.0%).
Open –
Pressing this button will set the Condenser Level Control Valve
Mode to Manual, if it had been in Auto. It will increase the current
Condenser Level Control Valve Command by an amount equal to the
Manual Increment, with a maximum of 100.0%.
Close –
Pressing this button will set the Condenser Level Control Valve
Mode to Manual if it had been in Auto and will decrease the current
Condenser Level Control Valve Command by an amount equal to the
Manual Increment, with a minimum of 0.0%.
Change
Setpoints
Admin
Provide ability to change the High Threshold, Low Threshold and
three PID gain settings.
YK-EP Style B Centrifugal Chiller 40