Form CP-MAPS-D12 with FX05, P/N 209341 Rev 4, Page 9
Space cooling discharge air setpoint (rCP) = 55ºF
During the Unoccupied Cycle the space setpoints will increase as follows:
Space Cooling Setpoint = (SSP + SCP + nSu) = 75°F + 1.8°F + 9°F = 85.8°F
(nSu default value = 9°F, adjustable from 0-35°F )
When the space temperature is more than SCP below the setpoint (73.2ºF),
the unit will switch to neutral air control. The control setpoint value will be the
dCH value.
The neutral air setpoint can be automatically adjusted based on outside air val-
ues. The discharge air setpoint will oat between the dCL value and the dCH
value depending upon the outside air conditions. In low humidity applications
where the unit may serve other mechanical equipment directly, it may be ben-
ecial to automatically adjust the setpoint to minimize the use of mechanical
equipment. NOTE: This function is not recommended for humidity sensi-
tive applications.
Automatic Changing of the Discharge Air
Setpoint Based Upon Outside Air
Discharge
Air Setpoint
Outside Air
Temperature
dCL = 55°F oC2 = 85°F
dCH = 65°F oC3 = 70°F
FIGURE 5 - Outside
Air Reset (dCL) allows
automatic changing
of discharge air
temperature based on
outside air temperature.
Variable
Name
Description
Defult Value
(Range)
dCH
Standard Discharge Air Setpoint (Primary Setpoint)
dCH is the value of the discharge air cooling setpoint when the
outside air temperature is at its coldest value to allow minimum
cooling. The discharge air temperature will not change to a
higher value than dCH regardless of the outside air tempera-
ture. If the reset option is disabled, the dCH becomes the pri-
mary neutral air cooling discharge air setpoint.
65ºF
(50 - 115ºF)
dCL
Outdoor Air Reset Option
dCL is the value of the discharge air cooling setpoint when the
outside air temperature is at its warmest value to allow maxi-
mum cooling. The discharge air temperature will not change to
a lower value than dCL regardless of the outside air tempera-
ture. The default value disables the option.
55ºF
(49 - 115ºF)
oC2
Outdoor Reset Dry Bulb Cooling – High Setting
The value of the outside air temperature corresponding to the
dCL coldest cooling setpoint value.
85ºF
(20 - 70ºF)
oC3
Outdoor Reset Dry Bulb Cooling – Low Setting
The value of the outside air temperature corresponding to the
dCH warmest cooling setpoint value.
70ºF
(-40 - 65ºF)
Disable
Making the dCL value higher than the dCH value disables this
functionality.
Disabled
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