JOHNSON CONTROLS
29
SECTION 2 - OPTIVIEW CONTROL CENTER INTRODUCTION
FORM 160.78-O2
ISSUE DATE: 5/22/2017
2
OVERVIEW
This screen displays all parameters related to the Head
Pressure Control feature. It also allows for setting of
the setpoints applicable to this feature.
If equipped with this optional feature, it must be en-
abled on the SETUP Screen. Once enabled, this screen
is accessible from the CONDENSER Screen.
The Condenser water flow animation will show flow
when the Condenser Liquid Flow Switch senses flow
is present.
A complete explanation of the Head Pressure Control
feature is contained in
YORK YMC
2
Service Manual
(Form 160.78-M2)
.
The following fields require login access
level of SERVICE. Service technicians re-
fer to YORK YMC
2
Service Manual (Form
160.78-M2) for operation instructions and
explanations of all programmable setpoints,
zone parameters and displayed values.
DISPLAY ONLY
Entering Condenser Liquid Temperature
Displays the temperature of the liquid as it enters the
standard condenser tube bundle.
Leaving Condenser Liquid Temperature
Displays the temperature of the liquid as it leaves the
standard condenser tube bundle.
Delta P
Displays the pressure difference between the condens-
er and evaporator (condenser minus evaporator). This
is also called the Head Pressure.
Head Pressure Setpoint
Displays the active Head Pressure Setpoint to which
the head pressure is being controlled.
Control Valve Command
Displays the position command being sent to the con-
trol valve. Displayed over the range of 0.0% to 100%.
The actual value of the output signal for a given error
depends on whether the PID OUTPUT setpoint is set
to DIRECT or REVERSE. If set to DIRECT, the 0.0%
output will be at minimum; the 100% output will be at
maximum. If set to REVERSE, the 0.0% output will
be at maximum; the 100% output will be at minimum.
Control Valve Control Mode
Displays whether the Control valve is in automatic or
manual control.
HEAD PRESSURE CONTROL SCREEN
LD14335a
FIGURE 9 -
HEAD PRESSURE CONTROL SCREEN
