kitControl-NightPurge

This component uses the two sets of temperature and humidity inputs to find the air supply with the least amount of heat when the Purge Enabled input is true.

NightPurge is available in Energy folder of the kitControl palette.

For inside and outside comparisons, you can select either temperature or enthalpy comparisons. There is also a low temperature check to protect against freezing.

Figure 46. NightPurge properties

Property	Value	Description
Temperature Facets	Config Facets window	Selects units and configures how the value displays: `units` defaults to temperature. `precision` defines the number of decimal places of temperature. `min` defines the lowest temperature allowed. `max` defines the highest temperature allowed. This configuration applies to the `Outside Temp`, `Inside Temp`, and `Low Temperature Limit` property values.
Humidity Facets	Config Facets window	Selects units and configures how the value displays: `units` defaults to percentage of relative humidity (%RH) . `precision` defines the number of decimal places of humidity percentage. `min` defines the lowest humidity allowed. `max` defines the highest humidity allowed. This configuration applies to the `Outside Humidity` and `Inside Humidity` property values.
Purge Enabled	StatusBoolean `true` or `false` (default) and null definition	`true` enables the night purge operation. `false` sets the `Free Cooling` output to the opposite of the `Free Cooling Command` (or `null`, if `Use Null Output` is set to `true`), and the `Current Mode` slot value is `Disabled`. Often this slot is linked to a Not object sourced from a BooleanSchedule output. When null is checked, the value displayed defaults to the incoming value from the device. If you remove the check mark you can configure the `In` value.
Outside Temp	number of degrees of temperature (defaults to 0.0F) and null definition	Defines the current outside air temperature. This input must be valid for this object to function. When null is checked, the value displayed defaults to the incoming value from the device. If you remove the check mark you can configure the `In` value.
Outside Humidity	percentage of relative humidity (defaults to 0.0 %RH) and null definition	Defines the current outside air humidity. This input must be valid for this object to function. When null is checked, the corresponding value defines the default when a calculation returns null.
Inside Temp	number of degrees of temperature (defaults to 0.0F) and null definition	Defines the current inside air temperature. This input must be valid for this object to function. When null is checked, the value displayed defaults to the incoming value from the device. If you remove the check mark you can configure the `In` value.
Inside Humidity	percentage of relative humidity (defaults to 0.0 %RH) and null definition	Defines the current inside air humidity. This input must be valid for this object to function. When null is checked, the value displayed defaults to the incoming value from the device. If you remove the check mark you can configure the `In` value.
Low Temperature Limit	number of degrees of temperature (defaults to 0.0F) and null definition	Provides freeze protection. When null is checked, the value displayed defaults to the incoming value from the device. If you remove the check mark you can configure the `In` value.
Night Setpoint	number of degrees of temperatur (defaults to 0.0F) and null definition	Defines the night temperature setpoint, at or below which free cooling is not applied. Instead, the `Current Mode` is set to `Satisfied`. When null is checked, the value displayed defaults to the incoming value from the device. If you remove the check mark you can configure the `In` value.
Outside Enthalpy	read-only energy measured in BTUs per pound to two decimal places (defaults to 0.00 BTU/lb)	Displays the calculated outside air enthalpy.
Inside Enthalpy	read-only energy measured in BTUs per pound to two decimal places (defaults to 0.00 BTU/lb)	Displays the calculated inside air enthalpy.
Free Cooling [output]	read-only StatusBoolean `true` or `false` (default)	Displays the value of the `Free Cooling Command` when free cooling should be used. Otherwise, it displays the opposite state, or `null` (if `Use Null Output` is set to `true`). The component sets the `Free Cooling` output to `false` if `outside >= inside` or `true` if `outside = Night Setpoint`.
Current Mode	read-only value (defaults to `Disabled`	Indicates which of the following modes this object is currently in: `Disabled` indicates that `Purge Enabled` is `false`. `Free Cooling` `No Free Cooling` indicates that free cooling is not available. `Low temperature` indicates that Outside Temp is below the Low Temperature Limit and free cooling is disabled. `Input error` indicates that a temperature or humidity is invalid (down, fault, etc.) and free cooling is disabled. `Satisfied` indicates that inside temperature is below the `Night Setpoint` and free cooling is disabled.
Setpoint Deadband	degrees of temperature to a single decimal place (defaults to 1.0F)	Applies temperature `Setpoint Deadband` when inside temperature falls below `Night Setpoint` before free cooling can be enabled.
Threshold Span	number to two decimal places (defaults to 1.0)	Defines a value. The difference between the `Inside Enthalpy` and the `Outside Enthalpy` must be greater than this value before the component enables free cooling.
Use Enthalpy	StatusBoolean `true` (default) or `false`	`true` enables the use of enthalpy to determine if free cooling is available. `false` uses outside and inside temperature to decide.
Free Cooling Command	StatusBoolean `true` (default) or `false`	Configures `Free Cooling` output. `true` indicates that free cooling is available, therefore `Free Cooling` output should be set to `true`. `false` indicates that free cooling is not available, therefore `Free Cooling` output should be set to `false`.
Use Null Output	StatusBoolean `true` (default) or `false`	Configures `Free Cooling` output. `true` sets the null flag for `Free Cooling` output when free cooling is not available. `false` ignores the null flag for `Free Cooling` output.

kitControl-NightPurge

Figure 46. NightPurge properties

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