Digistat3 Installation

[Terstons_girl]

Hi guys,

I know this topic has been covered before, and I've checked the postings but I'm being very thick and still can't work out how my old thermostat wiring works. I have a Honeywell dial room thermostat and want to fit a new Digistat3 digital thermostat. My old thermostat has 3 wires (brown-1, blue-2 and yellow/green-3) and the new thermostat requires a Common-1, Demand-3 and Satisfied-2 wires. Which wires do I fit to the new thermostat? The instructions say not to fit a Neutral or Earth to the new one - but I only have three wires in total so don't I need all of them? I wouldn't assume that the colours of the old wires are necessarily live, neutral and earth as I assume they may have just used a three core wires cos they needed three wires to the boiler. Any help before Christmas gratefully received!!

Terstons_girl

 

[breezer]

Your assumption is totaly wrong.

its not live, neutral and earth

its live swithced live and earth

its going to be hit and miss but try

1 & 3 or 1 & 2

in either case use the red and black, put the earth in a choc block only