Potterton EP2002 to Nest

[red_g00ner]

Am struggling to work out the wireing for the nest heat link.

I have the following:
Potterton Suprima 80
Potterton EP2002
Wired thermostat in another room
Hot water tank upstairs
HW and CH work separately

I've looked at the wiring for the EP2002 but can't tell what should be connected to what.

Link to pic
https://ibb.co/k0gZV6

Any advice would be appreciated

 

[Gas2Air]

Am struggling to work out the wireing for the nest heat link.

I have the following:
Potterton Suprima 80
Potterton EP2002
Wired thermostat in another room
Hot water tank upstairs
HW and CH work separately

I've looked at the wiring for the EP2002 but can't tell what should be connected to what.

Link to pic
https://ibb.co/k0gZV6

Any advice would be appreciated

It's confusing because the EP were used as a wiring centre. I would suspect your roomstat is wired back into it. Neutrals are linked in the picture, so are Earths. You have 1 Live, which is linked to 5. 3 is hot water on, 4 is heating on. (or vice versa as I can't remember). Not for a DIY to wire if you're not confident.