Adding a zone to a heating system

[B17NNS]

My mum has a relatively new heating system (couple of years old) with a Worcester Bosch combi.

Her kitchen is opened up into a conservatory and is always quite cold in the winter.

What I'd like to do is put the radiator in the conservatory in it's own zone with its own stat.

I'm relatively handy with a spanner but I haven't a clue what I need to buy and what I need to what to do with it.

Help

[silversurfer1]

Ideally you will need two zone valves and two channels from a programmer. Look up "S" plan wiring but basically signal from programmer goes through room stat and opens zone valve, zone valve switches micro switch that lets power through to fire boiler once valve is open. This allows boiler to be fired if either both or just one of the valves are open.

You will also need a bypass but id be quite sure your boiler has a built in one.

Power on signal from channel one on the programmer and room stat will open zone valve one and fire main heating system.

Power on signal from channel two on the programmer and room stat will open zone valve two and fire boiler for conservatory only.

Good luck

SS

[B17NNS]

Cheers. Boiler is a Greenstar 30SI. Think this has a built in bypass.

So the only plumbing required would be fitting two zone valves? Flow from boiler splits into two, one flow feeding conservatory, other flow feeding rest of house, zone valve on each flow. Returns left as is.

Existing programmer/timer/stat as is. Add standard room stat in conservatory.

Edited by B17NNS on Wednesday 17th September 23:39

[silversurfer1]

Pretty much yep thats it. If you and the conservatory on at different times you will new a new programmer as i would guess the existing will be a single channel being its a combi

SS

[B17NNS]

It's a Honeywell CM707. Presumably that could be swapped for a twin channel and the CM707 moved to the conservatory?