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1.800.627.4499
DN-Series Integrated Programmable Controls
DOAS
SYSTEM MONITORING
13.5.5.3 Cooling Control
The cooling control type is located at Multistate Input 5 “CLG_ControlType_BN.” The valid
values are 1 = 1 Stage, 2 = 2 Stage, 3 = Cold Water Modulating, 4 = VRF, 5 = PDX. The
setpoint is Analog Value 56 “Occ_CLG_SetP.Val.”
The cooling output statuses are the following:
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Binary Input 19 “Cooling_Enable_1.Val” for stage one or modulating types where the demand
is greater than 0
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Binary Input 20 “Cooling_Enable_2.Val” for stage two
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Analog Input 33 “Cooling_Command.Val” shows a percentage for the 0–10V output.
13.5.5.4 Dehumidification Control
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If the cooling is currently being used for dehumidification, Binary Input 61
“DehumidificationMode_ON” will be true.
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Analog Value 52 “HGRH_Coil_LAT_Setp.Val” is the setpoint for dehumidification by cooling.
The actual value is shown in Analog Input 29 “Cooling_LAT.Val” is the temperature coming
off the coil, if using reheat.
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The unit will reheat to Analog Value 57 “HGRH_Unit_LAT_Setp.Val” if reheating.
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Analog Input 62 “HGRH_Command.Val” will show the command for HGRH. If used.
13.5.5.5 Economizer Control
The economizer will be enabled when there is a call for cooling and the outdoor is more
favorable than the return air. In this case it will modulate the bypass damper to bypass the
enthalpic core and thus limit or inhibit the exchange of energy. The mechanical cooling is not
allowed until the bypass is open 100%. During this time the unit still uses 100% outdoor air.
Economizing is allowed when both of the following Are below their limit:
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Analog Value 52 “Economizer.Econ_Low_OA_Temp_Limit”
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Analog Value 58 “Economizer.Econ_Low_RA_Temp_Limit”
The damper will modulate using PI Control set in the controller when the OA is less than the
difference value specified as follows:
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If using the temperature economizer type, the value used is Analog Value 51
“Econ_Temp_Diff”
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If using the enthalpy economizer type, the value used is Analog Value 53
“Economizer.Econ_Hysteresis”
You can view the status through Binary Input 60 “Econ_Active” to see if the economizer is
active. The bypass damper position is viewed at Analog Input 59 “Bypass_Command.Val.”
13.5.5.6 Unoccupied Control
If optional recirculation dampers are present, the unit will operate in unoccupied mode
according to the following settings:
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Binary Value 63 “OnOffUnitMng.BMSUnocc” allows you to put the unit in unoccupied mode.
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The supply fan will either run continuous or on a call for heat or cooling as set in the
controller. It will run at a speed set in Analog Value 64 “SF_UnoccFlowSetP.Val.”
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It will maintain the Analog Value 66 “Unocc_CLG_SetP.Val” and Analog Value 71
“Unocc_HTG_SetP.Val.”
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The status of the recirculation damper is seen at Binary Input 49 “Recirc_Damp.Val.”
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The unoccupied statuses can be viewed in Binary Input “67 “Unocc_Mode,” Binary Input “68
“Unocc_HTG,” and Binary Input “69 “Unocc_CLG.”
