PRCH_PreCtrlHtg
The PRCH_PreCtrlHtg macro provides:
- Heating or changeover pre-control with optional pump, valve and changeover output for a 2-pipe system.
For changeover control you need both, the cooling and the heating pre-control macros.
- Freeze protection at low outside air temperatures
- Options to connect external bus systems to the pre-control circuit
See Programming Hints for the procedures to connect SERVAL (XL10), LYNX (SPYDER) or MERLIN (IRM) controllers to LON or BACnet systems, programmed with CARE and Niagara systems programmed with COACH NX.
The macro must be connected to the HVAC_Mode” output of the macro “SWM_SummerWinterMode” where the outside air temperature limits for heating and cooling control can be set.