Ventilation

The Room Type Manager Ventilation panel contains controls used to define the room ventilation properties for rooms of the selected room type. Ventilation is the purposeful flow of outside air into a thermal zone in order to provide some amount of non-mechanical cooling.

Note: By default, a ventilation component containing the data defined in this panel is added to the room hierarchy in the project tree dialog box for all subsequently created instances of the selected room type. The ventilation data can be edited for individual rooms by using the corresponding ventilation data controls found on the Properties For: Ventilation dialog box.

Setting	Description
New	Used to create new ventilation sub-components for rooms of the selected room type. (New) ventilation — Whenever the New button is pressed, and new ventilation sub-component panel is created. The controls provided for it can be set independent of the other ventilation sub-components in the Properties For: Ventilation dialog box. Delete icon — Used to delete the ventilation sub-component.
Name	Used to enter a name for the ventilation sub-component.
Design flow rate calculation method	Contains controls used to select a design flow calculation method for the selected room’s ventilation sub-component. When one is selected, a corresponding method value field is enabled under the Design flow rate calculation method control. Flow rate per room — When selected, the method used is a direct insertion of the design volume flow rate. A flow rate must be entered for the Design flow rate control which is enabled by this selection. Flow rate per area — When selected, the method used is a factor per floor area of the zone (room floor area is calculated as a portion of the total zone floor area). A flow rate must be entered for the Flow rate per zone floor area control which is enabled by this selection. Flow rate per person — When selected, the method used is a factor per persons occupying the room. A flow rate must be entered for the Flow rate per person control which is enabled by this selection. Air changes per hour — When selected, the method used is the number of air changes per hour for the infiltration amount. The infiltration amount must be entered for the Air changes per control which is enabled by this selection.
Design flow rate	Used to enter a flow rate when the Flow rate per room Design flow calculation method is selected. The Design flow rate denotes the full design volume flow rate which is the maximum amount of infiltration expected at design conditions.
Flow rate per zone floor area	Used to enter a flow rate when the Flow rate per area Design flow calculation method is selected. The Flow rate per zone floor area is used to determine the maximum amount of infiltration expected at design conditions for the specific area occupied by the selected room type within the zone.
Flow rate per person	Used to enter a flow rate when the Flow rate per person Design flow calculation method is selected. The Flow rate per person is used to determine the maximum amount of infiltration expected at design conditions for the number of people occupying the selected room type.
Air changes per hour	Used to enter the number of air changes per hour rate when the Air changes per hour Design flow calculation method is selected. The Air changes per hour is used to determine the maximum amount of infiltration expected at design conditions based on the number of times in each hour the air volume changes due to infiltration.
Schedule	Used to select an occupancy schedule for the selected room’s ventilation sub-component.
Ventilation type	Contains controls used to select the nature of the ventilation occurring for the selected room’s ventilation sub-component. Natural — Ventilation occurs naturally through open windows and doors based on environmental factors such as wind and pressure differences between the inside and outside of the thermal zone. Natural ventilation does not require fan energy, and values for fan pressure and efficiency are ignored. Intake — Ventilation occurs by moving air from the outside to the inside using a fan. Values for fan pressure and efficiency are used to determine the amount of energy consumed as well as the amount of heat introduced by the fan. Exhaust — Ventilation occurs by moving air from the inside to the outside using a fan. Values for fan pressure and efficiency are used to determine the amount of energy consumed.
Fan pressure rise	Used to enter a pressure rise experienced across the fan used for the selected room’s ventilation sub-component.
Fan total efficiency	Used to enter a total fan efficiency factor (a decimal number between 0.0 and 1.0) for fans used for the selected room’s ventilation sub-component.
Constant term coefficient	Used to enter a modifying parameter (a function of environmental conditions) used to solve the ventilation equations performed for the selected room’s ventilation sub-component. The Constant term coefficient is constant under all conditions, and is therefore dimensionless.
Temperature term coefficient	Used to enter a modifying parameter (a function of environmental conditions) used to solve the ventilation equations performed for the selected room’s ventilation sub-component. The Temperature term coefficient is modified by the temperature difference between the outdoor and indoor air dry-bulb temperatures.
Velocity term coefficient	Used to enter a modifying parameter (a function of environmental conditions) used to solve the ventilation equations performed for the selected room’s ventilation sub-component. The Velocity term coefficient is modified by the speed of wind being experienced outside the building.
Velocity squared term coefficient	Used to enter a modifying parameter (a function of environmental conditions) used to solve the ventilation equations performed for the selected room’s ventilation sub-component. The Velocity squared term coefficient is modified by the square of the speed of wind being experienced outside the building.