Originally Posted by
DBMandrake
But that's not what was being talked about - you were implying that you could simply leave out the HR92 for the zone the controller was sensor for and have the controller as a sensor with no zone actuator of any type, and still fire the boiler - which you can't. Except in the special single zone mode, you always have to have at least one actuator that is specific for each zone.
A BDR91 and zone valve CAN be the actuator for the zone (as I mentioned) provided that the zone valve only controls the room being monitored by the sensor - it's no good trying to use a zone valve for an entire floor unless you don't want any individual control of rooms.
One heating zone is a special case - you can do that with no actuators except a boiler relay. However as soon as you have two or more zones you can't do this.
No you can't do that, because you must have at least one actuator for the zone - a temperature sensor is not enough.
I don't know about earlier models but the Wi-Fi model won't even let you create a zone without an actuator in it if you try. And if you try to unbind existing HR92's from an already configured zone, leaving none in the zone you'll get comms errors after a few hours when the controller wonders what happened to the missing HR92(s).