Could control individual radiators using thermal actuators controlled using Sonoff basic wifi switches to turn on and off. Actuators based on heating wax should be silent if a little slow to respond. 3-4 minutes to open or close.
- Thermal Actuator [£12.50]
- Sonoff Basic or [£5]
- Sonoff TH combining Temperature and humidity sensor with switch. [£15]
Disadvantages of this system are:
- need mains power near every radiator that needs to be controlled, typically sockets are not near radiators.
- Need one on every radiator in a room
- If the system fails, have to manually switch each basic on, to get any heat to the radiator.
Alternative is to install motorised valves to zone the heating system, again controlled by Sonoff basics (or just cabled to the heating controller). These would typically be hidden under floorboards.
- Need to know the complete layout of the heating pipes to be able to decide where to insert the values.
- Likely need to install more plumbing to create zones.
- As hidden under floorboards, failure of the valves would cut heat to that zone until it is replaced.
- Need to lift floorboards, ground floor pipes are under concrete so no scope to install.
- Only useful if areas can be zoned, which rooms to group together?