Dehum fan speed in fixed variable and single zone VAV - Johnson Controls - LIT-12011950 - Building automation software - Smart Equipment Controller - 5.0

Smart Equipment Controls Sequence of Operation Technical Bulletin

Product name
Smart Equipment Controller
Document type
Technical Bulletin
Document number
LIT-12011950
Version
5.0
Revision date
2024-06-06
Product status
Active

When in Hot Gas Reheat, a separate fan speed provides adequate airflow.

Equipment Impacted

Systems utilizing Fixed Variable Speed fan configurations and single-zone VAV units.
Note: No other fan configurations are capable of supporting this functionality

Implementation Method

A new configuration point has been added to allow all systems using Fixed Variable Speed fan configurations or single-zone VAV units to set a different speed for use with Hot Gas Reheat. This speed is enforced when the system is operating one compressor with Hot Gas Reheat active. If additional compressors are energized, the appropriate 2nd, 3rd, or 4th stage fan speed will take priority.
Note: For systems requiring additional outputs be energized in conjunction to C1 in order to fully load the HGR circuit, these additional stages ARE NOT considered such that they would override the dehumidification fan speed.