Johnson Controls YORK OM Titan, Operating Instructions Manual

Page: 35 / 138

JOHNSON CONTROLS
35
FORM 160.72-O1 (810)
overvieW
This screen displays a cutaway view of the Hot Gas
Bypass Valve. All setpoints relating to Hot Gas By-
pass control are maintained on this screen. Also, relat-
ed Hot Gas Bypass control parameters are displayed
for reference. Through animation, the relative valve
position is displayed. In addition, the valve can be
manually operated.
displaY onlY
hot gas Bypass valve position
Displays the position of the Hot Gas Valve over the
range of 0% (closed) to 100% (fully open). The valve
position is animated, as well as the hot gas flow, if the
chiller is running and the hot gas valve is open. When
the actual position is 0% to 19%, the valve is shown
fully closed and no gas flow is displayed. When ac-
tual position is 20% to 39% the valve is shown 25%
open. When actual position is 40% to 59%, the valve is
shown 50% open. When actual position is 60% to 79%,
the valve is shown as 75% open. Positions greater than
79% are shown as full open.
pre-rotation vanes position
Displays the position of the Pre-Rotation Vanes over
the range of 0% (closed) to 100% (fully open).
delta p/p
A parameter that represents system differential or
HEAD. It is calculated as [(condenser pressure – evap-
orator pressure) / evaporator pressure].
Temperature differential
Displays the difference between the Leaving Chilled
Liquid Temperature and the Leaving Chilled Liquid
Temperature Setpoint. It is calculated by subtract-
ing the Leaving Chilled Liquid Temperature from the
Leaving Chilled Liquid Temperature Setpoint.
hot gas Bypass liquid injection solenoid
(led)
Indicates whether the Hot Gas Bypass Liquid Injection
Solenoid is energized. This should be energized when-
ever the hot gas bypass valve is open.
hoT gas BYpass sCreen
HOT GAS ByPASS SCREEN figure 9 -
3