Installation of Wireless Thermostat advice needed

[craigf]

Hi I would like to ask for some advice on the following,
I have a Sunvic Select 107 control unit fitted and wish to replace it with a new Celect wireless thermostat. the sunvic has 6 points to wire against on the backing plate.
1=N 2=L feeds in
3=brown
4=nil
5=blue
6=nil
label on rear states
1=N feed
2=L feed
3=Com switched with
4=Off
5=On
6=Nothing

The new one states 5 connections as follows
1=N
2=L linked to
3=
4=Heat on
5=Heat off

points 1 & 2 are not an issue, as I don't wish to damage the unit I need to know does my current point 5 (on) go to new point 4 and therefore my current point 4 goes to my new point 5. God I do hope someone understands, any help would be great, thanks

 

[EliteHeat]

Your current terminal 4 (heat off) is not currently connected and therefore you don't need to do anything with the old 4 to the new 5.

You will need to link 2 to 4 unless you need volt-free switching (which doesn't seem likely).

 

[craigf]

Many thanks for the reply I will give it a try, what is volt free switching as that is also in the new instructions.

 

[D_Hailsham]

Your current terminal 4 (heat off) is not currently connected and therefore you don't need to do anything with the old 4 to the new 5.

Agreed

You will need to link 2 to 4 unless you need volt-free switching (which doesn't seem likely).

I think you mean link 2 to 3. If you link 2 to 4 you bypass the switch completely so the boiler will be on 24/7.

Re Volt Free switching

Some boiler, particularly older ones run when 230v is supplied to them. This is done by supplying 230 volt to the programmer/thermostat which then supplies the boiler when the thermostat contacts close.

Many modern boilers have a permanent 230V supply. The boiler will run when two terminals on the boiler are connected together. This is done by wiring these terminals to the thermostat Common and On terminals. In this case the thermostat is not supplying 230V, so the thermostat terminals are volt-free.

 

[craigf]

Thanks for the relies I have got it working fully. I place the blue wire from old point 5 to new point 4 and the brown wire from old point 3 to new point 5, new point 2 I linked with new point 3, all works as it should. Again thanks