New Zone on central heating.

[Rampage]

I have just fitted a new Zone on the central heating and need to wire it up. The new Zone will be controlled by a Carel S90 digital thermostat. Where the Zone valves have been fitted, the timer/thermostat cable runs past, so I've cut into the cable and it has 2 lives, earth and neutral. Because we hardly ever use hot water the existing timer is always in the OFF position. This means there isn't a constant live in the cable that can be used to power the new thermostat. There isn't a constant live at the boiler either.
So I need a live to power the new thermostat, what's the best way of getting power to it?

 

[MarkieSparkie]

Run a separate permanent live conductor from you heating wiring centre (big junction box) to the thermostat. Don't be tempted to pinch it from elsewhere.

 

[Rampage]

I've currently not got a large junction box as there were no valves originally in the system. I'm going to run a permanent live from the programmer I think.

Thanks.