105
YORK INTERNATIONAL
FORM 100.50-NOM1 (604)
7
ECONO/EXHAUST SYSTEM
Exh Dmpr Pos For ON
This tells the control the Exhaust Air Damper posi-
tion at which to turn ON the Exhaust Fan for building
pres sure control using a modulated exhaust air damper
or VFD.
Exh Dmpr Pos For OFF
This tells the control the Exhaust Air Damper posi-
tion at which to turn OFF the Exhaust Fan for build-
ing pres sure control using a modulated exhaust air
damper or VFD.
OA Dmpr Pos For ON
This tells the control the Economizer Air Damper
(out door air damper) position at which to turn ON
the Ex haust Fan.
OA Dmpr Pos For OFF
This tells the control the Economizer Damper (out-
door air damper) position at which to turn OFF the
Exhaust Fan.
OAH Sensor Enable
This tells the control that an outside air humidity
(OAH) sensor is present and enabled for use.
The enthalpy control function is self-con
Þ
guring to
make use of the available sensors to calculate the best
available decision strategy for free cooling avail abil i ty.
For example, if it detects that OAT and OAH, and RAT
and RAH sensors are all connected and re li able, it will
self-con
Þ
gure for differential enthalpy op er a tion. If
one of the return air sensors should fail, the control
will recon
Þ
gure for outside enthalpy operation, etc.
When available and reliable, the RAT, RAH, and OAH
sensors will be used for enthalpy control whether or
not they are enabled.
Should a sensor fault be detected for the OAH sensor,
the fault is displayed and recorded only if the OAH
Sensor Enable is ON.
If the controller is networked, the network can be pro-
grammed to share the OAT and OAH sensed values
with other controllers connected to the network or to
receive these values from the network.
RAH Sensor Enable
This tells the control that a return air humidity (OAH)
sensor is present and enabled for use.
The control will self-con
Þ
gure for enthalpy control
based on the sensor availability as described above in
above in
Outside Air Humidity Sensor Enable (OAH
Sen sor Enable).
Should a sensor fault be detected for the RAH sensor,
the fault is displayed and recorded only if the RAH
Sensor Enable is ON.
Exhaust Cntrl Offset
This setting tells the control what the control band is
for the building pressure control. This setting is a plus
or minus value to be added or subtracted to the
Build-
ing Pressure Setpoint
. For the proportional exhaust
sys tems, this setting is the proportional band for the
control loop. For the on/off exhaust system, this set-
ting es tab lish es the turn ON and turn OFF points for
the exhaust fan.
Economizer Enable
This setting tells the control to allow Economizer Op-
er a tion to occur. If this setting is set to ON, the control
will operate the economizer normally. If this setting is
set to OFF, the control will not operate the economizer,
even if the unit is equipped with economizer hardware.
However, all ventilation options will be operated nor-
mal ly, regardless of this setting.
SAT Econo Loading
This tells the control that it is to use Economizer
Load ing to control excessive SAT when economizer
op er a tion is calculated to be not available.
Power Exhaust Enable
This tells the control to enable or disable the power
exhaust system. If the unit is con
Þ
gured with no Power
Exhaust (See Power Exhaust Con
Þ
guration), the set-
ting will be ignored.