CONTROLLER:OUTDOORAIR

Controller to set the outdoor air flow rate for an air loop. Control options include fixed, proportional, scheduled, economizer, and demand-controlled ventilation.

Name

Type: alphanumeric

Relief Air Outlet Node Name

Type: node

Return Air Node Name

Type: node

Mixed Air Node Name

Type: node

Actuator Node Name

Type: node
Outdoor air inlet node entering the first pre-treat component if any

Minimum Outdoor Air Flow Rate

Type: real number
If there is a Mechanical Ventilation Controller (Controller:MechanicalVentilation), note that this value times the Minimum Outdoor Air Schedule is a hard minimum that may override DCV or other advanced OA controls.
Unit: m3/s

Maximum Outdoor Air Flow Rate

Type: real number
Unit: m3/s

Economizer Control Type

Type: choice (FixedDryBulb, FixedEnthalpy, DifferentialDryBulb, DifferentialEnthalpy, FixedDewPointAndDryBulb, ElectronicEnthalpy, DifferentialDryBulbAndEnthalpy or NoEconomizer)
Default: NoEconomizer

Economizer Control Action Type

Type: choice (ModulateFlow or MinimumFlowWithBypass)
Default: ModulateFlow

Economizer Maximum Limit Dry-Bulb Temperature

Type: real number
Enter the maximum outdoor dry-bulb temperature limit for FixedDryBulb economizer control type. No input or blank input means this limit is not operative. Limit is applied regardless of economizer control type.
Unit: C

Economizer Maximum Limit Enthalpy

Type: real number
Enter the maximum outdoor enthalpy limit for FixedEnthalpy economizer control type. No input or blank input means this limit is not operative Limit is applied regardless of economizer control type.
Unit: J/kg

Economizer Maximum Limit Dewpoint Temperature

Type: real number
Enter the maximum outdoor dewpoint temperature limit for FixedDewPointAndDryBulb economizer control type. No input or blank input means this limit is not operative. Limit is applied regardless of economizer control type.
Unit: C

Electronic Enthalpy Limit Curve Name

Type: list of objects (CURVE:QUARTIC, CURVE:EXPONENTIALDECAY, CURVE:DOUBLEEXPONENTIALDECAY, CURVE:FUNCTIONAL:PRESSUREDROP, CURVE:SIGMOID, CURVE:RECTANGULARHYPERBOLA1, CURVE:CUBIC, CURVE:QUADRATIC, CURVE:EXPONENTIALSKEWNORMAL, CURVE:LINEAR, TABLE:LOOKUP, CURVE:RECTANGULARHYPERBOLA2 or CURVE:EXPONENT)
Enter the name of a quadratic or cubic curve which defines the maximum outdoor humidity ratio (function of outdoor dry-bulb temperature) for ElectronicEnthalpy economizer control type. No input or blank input means this limit is not operative Limit is applied regardless of economizer control type.

Economizer Minimum Limit Dry-Bulb Temperature

Type: real number
Enter the minimum outdoor dry-bulb temperature limit for economizer control. No input or blank input means this limit is not operative Limit is applied regardless of economizer control type.
Unit: C

Lockout Type

Type: choice (NoLockout, LockoutWithHeating or LockoutWithCompressor)
Default: NoLockout

Minimum Limit Type

Type: choice (FixedMinimum or ProportionalMinimum)
Default: ProportionalMinimum

Minimum Outdoor Air Schedule Name

Minimum Fraction of Outdoor Air Schedule Name

Maximum Fraction of Outdoor Air Schedule Name

Mechanical Ventilation Controller Name

Type: list of objects ( or CONTROLLER:MECHANICALVENTILATION)
Enter the name of a Controller:MechanicalVentilation object. Optional field for defining outdoor ventilation air based on flow rate per unit floor area and flow rate per person. Simplified method of demand-controlled ventilation.

Time of Day Economizer Control Schedule Name

Type: list of objects (SCHEDULE:FILE, EXTERNALINTERFACE:SCHEDULE, SCHEDULE:YEAR, EXTERNALINTERFACE:FUNCTIONALMOCKUPUNITIMPORT:TO:SCHEDULE, SCHEDULE:CONSTANT or SCHEDULE:COMPACT)
Optional schedule to simulate "push-button" type economizer control. Schedule values greater than 0 indicate time-of-day economizer control is enabled. Economizer control may be used with or without the high humidity control option. When used together, high humidity control has priority over economizer control. If the field Economizer Control Type = NoEconomizer, then this option is disabled.

High Humidity Control

Type: choice (Yes or No)
Optional field to enable modified outdoor air flow rates based on zone relative humidity. Select Yes to modify outdoor air flow rate based on a zone humidistat. Select No to disable this feature. If the field Economizer Control Type = NoEconomizer, then this option is disabled.
Default: No

Humidistat Control Zone Name

Type: list of objects ( or ZONE)
Enter the name of the zone where the humidistat is located. This field is only used when the field High Humidity Control = Yes.

High Humidity Outdoor Air Flow Ratio

Type: real number
Enter the ratio of outdoor air to the maximum outdoor air flow rate when modified air flow rates are active based on high indoor humidity. The minimum value must be greater than 0. This field is only used when the field High Humidity Control = Yes.
Default: 1.0

Control High Indoor Humidity Based on Outdoor Humidity Ratio

Type: choice (Yes or No)
If No is selected, the outdoor air flow rate is modified any time indoor relative humidity is above the humidistat setpoint. If Yes is selected, the outdoor air flow rate is modified any time the indoor relative humidity is above the humidistat setpoint and the outdoor humidity ratio is less than the indoor humidity ratio. This field is only used when the field High Humidity Control = Yes.
Default: Yes

Heat Recovery Bypass Control Type

Type: choice (BypassWhenWithinEconomizerLimits or BypassWhenOAFlowGreaterThanMinimum)
BypassWhenWithinEconomizerLimits specifies that heat recovery is active only when the economizer is off because conditions are outside the economizer control limits BypassWhenOAFlowGreaterThanMinimum specifies enhanced economizer controls to allow heat recovery when economizer is active (within limits) but the outdoor air flow rate is at the minimum.
Default: BypassWhenWithinEconomizerLimits