Vav System - York eco2 050 Installation Operation & Maintenance

Parameter Description and Options
Cooling Lockout OAT
This is the Outside Air Temperature Setpoint that the
control will use to lock out Cooling when the OAT is
below this setpoint. A one-degree hysteresis is to be
used on each side of the setpoint.
Cooling SAT Alarm
The SAT must be below this setpoint when all stages
of compression are operating and after 60 minutes
has elapsed since the last compressor was energized.
If this does not happen, the control will declare a
Cooling SAT Failure Alarm. Disabled if Setpoint =
0°F. This item should always be disabled by placing
the set point to 0°F.
Heating SAT Alarm
The SAT must be above this setpoint when all steps
of heating are operating and after 20 minutes have
elapsed since the last heating step was energized. If
this does not happen the control declare a Heating
SAT Failure Alarm.

VAV SYSTEM

Duct Pres sure Limit
This parameter is applicable only to VAV mode of
op er a tion and controls at what static pressure to shut
down the unit if this setpoint is reached. This setpoint
is to insure that Supply Fan does not operate with a
problem that could cause ductwork damage. When
the stat ic pres sure reaches this setpoint:
• The control will drive the Supply Fan control
output to zero.
• If there is no change in static pressure after 20
seconds, the control will generate a High Duct
Stat ic fault and shut down the unit.
VAV Occupied Heat
This unit setup selection tells the control to allow
VAV Occupied Heating to occur if necessary. When
this set ting is set to ON, full heating will be energized
when either:
• The thermostat W1 or W2 signal is received, or
• The space temperature falls below the VAV Set-
point for SAT Reset by more than 2°F.
104
OA SAT Reset
This setting will tell the control to reset the SAT
set point on VAV units based on the Outside Air tem-
per a ture instead of Space temperature. Outside Air
SAT reset will only be allowed when the setting VAV
Op er a tion With Thermostat is set to OFF. This func-
tion can be used for Space Sensor and Stand Alone
op er a tion.
SAT Temper Enable
When SAT Tempering Enable is ON, the control will
use tempering to increase the no demand stability of
heating or cooling. SAT Tempering must be avail-
able for SAT Tempering to function. This conÞ gura-
tion set ting will be ignored if SAT Tempering is not
available.
VAV With Thermostat
This parameter is applicable only to VAV mode of
op er a tion. If this option is selected ON, it tells the
control that a Thermostat in a selected space is used
to reset the SAT in cooling and to control heating. If
this option is selected OFF, the control assumes that a
Space Sen sor in a selected space is used to reset SAT
in cooling and to control heating and self-conÞ gures
into this mode if the Space Sensor signal is reliable.
If the Space Sen sor signal is not reliable (e.g. sensor
is not connected), the control will self-conÞ gure to
stand-alone operation.
VAV Control Offset
The VAV Control Offset parameter is used to adjust the
compressor staging offset and is used in con junc tion
with the VAV Cool High Temp and VAV Cool Low
Temp setpoints on VAV units.
FlexSys Dewpt Reset
The FlexSys Dewpt Reset will tell the control that a
FlexSys Under-Floor Humidity (FLEXRH) and Un-
der-Floor Slab Temperature sensors are present and
en abled for use. This setting will allow Evaporator
Dis charge Air Temperature Reset.
If this setting is enabled, both the FlexSys Under-
Floor Humidity (FLEXRH) and Under-Floor Slab
Tem per a ture sensors must be installed and reliable
or faults shall be generated. If this setting is dis abled,
alarms will not be generated for these two sensors and
active faults will be cleared.
FORM 100.50-NOM1 (604)
YORK INTERNATIONAL