wiring up a programmable room stat to override programmer?

[liverpoolboy]

Ok bit of a quick question:

Bought a programmable room stat to replace a normal type one. My old one has 3 wires and the new one only requires 2 (the neutral is not required). It is battery powered also.

How do I wire it up to override the programmer? Is there a plan for this like the S PLAN and Y PLAN wiring diagrams that are available to help?

 

[shambolic]

Hard to tell without knowing the make and model of old and new type.
But possibly The batteries will do the clock and screen functions leaving the 2 wires as your live in and out.
You need to give more info though!

 

[liverpoolboy]

well the new one is sunvic and the old one was honeywell.

the thing is, surely i can just swap the common and require heat (demand) wires overand mayeb remove the neutral?

i am not sure about how to wire it up to override the prgrammer, to bring on heating when the room stat wants it and not just when the programmer allows it to, if that makes sense?

 

[simond]

The way everyone else does it is to switch the programmer to 'constant' for CH. Thereafter, CH is invoked 100% of the time.

However, if this is too easy for you , just take the CH ON cable out of the programmer backplate and connect it to permanent live (eg: the supply to the programmer).