Room thermostat wiring

[DrunkenDuck]

Hi
I am attempting to exchange my existing room stat with a Drayton Digistat 3 .
I have a fully pumped Y plan system with a standard room stat at the moment. Wiring is through a honeywell 10-way junction box.
My existing stat has wires from terminals 2,4 and 5 plus earth
The new stat is asking for
1. Common
2. Heating Satisfied
3. Call for Heat
and no earth or neutral is required as its double insulated.

The only thing i'm not clear on is which three terminals on the 10-way block to use

Anyone offer any advice ???
Thanks in advance

steve

 

[breezer]

you say you are changing it, what wires have you at the other end, and how are they connected, you may also like to search the forum (electrics) as changing an existing room stat was answered there too

 

[DrunkenDuck]

Hi
The 3 existing wires come from the 10 way junction box from terminals 2,4,5 and are still connected to the existing stat at this time
will do a search also as suggested.....did try that but found nothing...will try again
thanks

 

[DrunkenDuck]

Found some more info through search
Think it might help but would like to call upon your wisdom if i fail

Thanks

Steve

 

[DrunkenDuck]

Back again
The existing stat has wires to 1,3 and 4
1. yellow from 5 in the junction box
3. red from no.4 ""
4. blue from no.2
also an earth at the back

No.2 in the junction is neutral
so i assume from the new stats instructions i use neither the neutral or the earth, leaving me only red and yellow
In testing Red and yellow are both live when stat requests heat but only red stays live when satisfied
so....Red to new stat number 1 common ??
yellow to no.3 call for heat
does this sound right ??

just want to be sure before i try
thanks

 

[breezer]

assuming the call for heat is normally open, it sounds good to me. (excepth you should put the earth in a choc bloc in case it is required in the future, similarly for the neutral

 

[supersparks]

are you sure its a neutral because it could be setup for a on and off system (the ch is told when it is too cold and too hot (not just when its too cold))