.Buildings.Obsolete.Controls.OBC.ASHRAE.G36_PR1.AHUs.SingleZone.VAV.Controller

Information

Block for single zone VAV control. It outputs supply fan speed, supply air temperature setpoints for heating, economizer and cooling, zone air heating and cooling setpoints, outdoor and return air damper positions, and valve positions of heating and cooling coils.

It is implemented according to the ASHRAE Guideline 36, Part 5.18.

The sequences consist of the following subsequences.

Supply fan speed control

The fan speed control is implemented according to PART 5.18.4. It outputs the control signal yFan to adjust the speed of the supply fan. See Buildings.Obsolete.Controls.OBC.ASHRAE.G36_PR1.AHUs.SingleZone.VAV.SetPoints.Supply for more detailed description.

Supply air temperature setpoints

The supply air temperature setpoints control sequences are implemented based on PART 5.18.4. They are implemented in the same control block as the supply fan speed control. The supply air temperature setpoint for heating and economizer is the same; while the supply air temperature setpoint for cooling has a separate control loop. See Buildings.Obsolete.Controls.OBC.ASHRAE.G36_PR1.AHUs.SingleZone.VAV.SetPoints.Supply for more detailed description.

Economizer control

The Economizer control block outputs outdoor and return air damper position, i.e. yOutDamPos and yRetDamPos, as well as control signal for heating coil yHeaCoi. Optionally, there is also an override for freeze protection, which is not part of Guideline 36. See Buildings.Obsolete.Controls.OBC.ASHRAE.G36_PR1.AHUs.SingleZone.VAV.Economizers.Controller for more detailed description.

Minimum outdoor airflow

Control sequences are implemented to compute the minimum outdoor airflow setpoint, which is used as an input for the economizer control. More detailed information can be found at Buildings.Obsolete.Controls.OBC.ASHRAE.G36_PR1.AHUs.SingleZone.VAV.SetPoints.OutsideAirFlow.

Zone air heating and cooling setpoints

Zone air heating and cooling setpoints as well as system operation modes are detailed at Buildings.Obsolete.Controls.OBC.ASHRAE.G36_PR1.AHUs.SingleZone.VAV.SetPoints.ModeAndSetPoints.

Revisions

• March 1, 2023, by Michael Wetter:
  Changed constants from 0 to 0.0 and 1 to 1.0.
  This is for #3267.
• June 20, 2020, by Jianjun Hu:
  Updated the block of specifying operating mode and setpoints.
  This is for #1893.
• March 10, 2020, by Jianjun Hu:
  Replaced the block for calculating the operation mode and setpoint temperature with the one from the terminal unit package. The new block does not have vector-valued calculations.
  This is for #1709.
• August 3, 2019, by David Blum & Kun Zhang:
  First implementation.