A zone can be configured in 4 different ways, so its behavior in antifreeze mode can be:
Never activate
Activated when the zone temperature drops below the zone's antifreeze set point
Activated when the external temperature falls below the global antifreeze set point for the external temperature
Trigger when point 2 and 3 occur simultaneously
For the external temperature antifreeze set and relative hysteresis see ANTIFREEZE MODE.
The Antifreeze Set for the zones can be set in Configuration 1 and is valid for all zones:
Note
When you choose to activate the zone in antifreeze based on the outside temperature only, the set point required for the zone will be 100°C.