Honeywell st9400c to Hive v3 smart

[Nasir A]

Hi everyone

I have just bought Hive v3 after lots of research as I'm expecting no rewiring at all...

Just having a couple questions before I start my installation

1) In my existing Honeywell st9400c, I can't see any wire in terminal 2 which is for CH off so which terminal shall I ignore on the Hive terminal plate?

2) do I have to disconnect the room thermostat connection from the electric box or can I just remove the room thermostat and put the safety clips on wires and tape them for safety?

I've attached the few pics for my references.

Thanks everyone for the advice in advance. I'll really appreciate your support...

 

[kerching]

You have, by the look of it, a Y plan system ( the work of the devil and all his little helpers)
But you've got it and are stuck with it. DONT PANIC

CH off is not required
You need HW on
HW off
CH on
Line
Neutral
Earth

Best option is to find the Wiring centre/joint box and get rid of the room stat by joining out the L and Switched L and remove the neutral
That way you can remove the now redundant room stat OR leave stat in place, don't touch Wiring centre, join heating call and switch wire together in the room stat and leave it. Most likely red and yellow BUt look in the stat manual to confirm. If it bursts into flames it ain't my issue as I'm not there

 

[Nasir A]

Thankyou so much for the detailed reply...really do appreciate. Would you be able to advice from the pic which 2 wires can be joined from the room thermostat as I don't want flames lol

Thanks once again for your support...much appreciated

 

[kerching]

Looks like 1&3 from the drawing i.e. Yellow and red
However I AM NOT THERE AND TAKE NO RESPONSIBILITY. THIS ADVICE IS WORTH EXACTLY WHAT YOU HAVE PAID FOR IT

"Well m'lud my house burned down coz I did what someone on the Internet told me to do" isn't a valid defence