Replace Potterton EP2 with Hive - advice required

[Mike MacDonagh]

I got great advice here when I replaced a Potterton EP2000 with Hive (thanks @stem) so now we've moved and I hope to repeat the trick but with a Potterton EP2 and a Sunvic thermostat. This one looks simpler and previous threads help but am I right with the following:
EP2 - match all wires to the Hive equivalent, except 5 which I should isolate?
Sunvic - join red and yellow and isolate blue?

Thanks in advance!

 

[Deleted member 267285]

As long as the red and yellow are live and switched respectively yes. The EP2 number 5 is a link wire, so not needed in the Hive, nor needed to be isolated.

 

[Mike MacDonagh]

Thanks Chris.
Yes, I should have included the wiring diagram for the Sunvic but you're right, the yellow is switched live and the red permanent live.
For wire 5 in the EP2, I'll just remove it then.
Appreciate the response and the work you put into looking at!

 

[stem]

Sounds good to me

As @CBW said just loose the link between L and 5. Hive has this link already made internally.

And yes the yellow and red are the live and switched live respectively.

Ideally you could trace the thermostat cable back to it's origin, disconnect it and then link the terminals where the red and yellow have just been removed from together so that they are electrically connected. Then you can remove the original cable and thermostat completely.

If you were just to join the red and yellow wires together, wiring regs require that an accessory be present to indicate the presence of live cables. So, the connection shouldn't just be buried in the wall and hidden. Which would mean either leaving the old thermostat in place, or replacing it with a junction box.

 

[stem]

Ha, @Mike MacDonagh you beat me to it by seconds.

 

[Mike MacDonagh]

Thanks @stem, that makes a lot of sense. I like a tidy solution, so I'll try to find and remove the thermostat cable but, if not, I'll replace the thermostat with a junction box, as you suggest.

 

[Mike MacDonagh]

Sorry for the delay - the replacement went OK and it all works well.
Thanks for the advice!