The Heating/cooling state determination (HCStaDtr) compares room temperature to current setpoints and checks whether any HVAC devices are under active PID control. The heating / cooling state is identified (Heating, Cooling, or Neither) and supplied to the BACnet object HCSta. The H/C status is also displayed on the room operating unit. Additional relevant BACnet objects (owned by other AFs) are shown in the table below.
To change status by temperature, the room temperature heating/cooling controllers must be inactive and the room temperature must be appropriate (high enough or low enough) to activate the switch-on delay timer, DlyOnHCChovr (Switch-on delay for heat/cool.changeover). See Configuration.
Description | Object | Pre-loaded Values |
---|---|---|
Room temperature setpoint shift | SpTRShft [RM TEMP SHFT] | 0.0 |
Present cooling setpoint for comfort | SpCCmf [CMF CLG STPT] | 75ºF (25ºC) |
Delta cooling setpoint for pre-comfort | DSpCPcf [STBY C DELTA] | 2ºF (1ºC) |
Present cooling setpoint for economy | SpCEco [ECO CLG STPT] | 85ºF (30ºC) |
Cooling setpoint for protection | SpCPrt [PROT CLG STPT] | 104 ºF (40ºC) |
Present heating setpoint for comfort | SpHCmf [CMF HTG STPT] | 70ºF (21ºC) |
Delta heating setpoint for pre-comfort | DSpHPcf [STBY H DELTA] | 2ºF (1ºC) |
Present heating setpoint for economy | SpHEco [ECO HTG STPT] | 55ºF (12ºC) |
Heating setpoint for protection | SpHPrt [PROT HTG STPT] | 45 ºF (7ºC) |
Present cooling setpoint | PrSpC [CLG STPT EFF] | ---- |
Present heating setpoint | PrSpH [HTG STPT EFF] | ---- |
Present operating mode | PrOpMod [OP MODE EFF] | Comfort |
Room operating mode | ROpMod [RM OP MODE] | Comfort |
Plant operating mode | PltOpMod [PLANT OPMODE] | Comfort |
Room temperature setpoint (for display on room unit) | SpTR [RM TEMP STPT] | ---- |
Room temperature | TR [RM TEMP EVAL] | ---- |