Wiring Drayton RTS8 Combo stat to Riva Combi

[Draughtsman]

The existing 3+E cable from the old Honeywell stat should be handy, even though I binned the stat itself.

I think that stat fig. 5 and Riva fig. 6.15 are the relevant guides here..

Stat Neutral N (blue wire) to neutral N in the mains power supply block
Stat Live L (red wire) to external controls terminal block 1 (minus link M)
Stat N LOAD to external control terminal block 3 (now also minus link M) using yellow cable (needs brown sleeve on stat end?)
Earth from stat E terminal to E in mains power supply terminal block.

What do you guys think?

 

[stem]

For a combi boiler, Fig 5 is the correct version.

Unfortunately you don't give any info about your Honeywell so I can't be more specific about its terminal numbers, but If you already have three used wires at the Honeywell, ie.

Live
Neutral
Switched Live

You simply move them to the connections at the RTS 8, that have the same function. No need to do anything at the boiler end.

Live = RTS 8 (terminal L)
Neutral = RTS 8 (terminal N)
Switched Live = RTS 8 (terminal 3)

 

[Draughtsman]

The new stat is the Drayton in the title.

The cable isn't wired in to either the combi or the new Drayton stat (see last image, of combi external control terminal block & mains supply terminal block, both showing no external control wiring).

 

[stem]

Your post says that you have removed an old Honeywell thermostat and want to replace it with an RTS8. It's easier just to swap them over rather than change anything at the boiler end.

If you had given model details of the Honeywell (there are many different Honeywell thermostats) and where each of the three wires that went to it were connected, I would have told you where to reconnect connect the aforesaid wires to the RTS8

However, I see that you have binned the old stat, so if you can't remember where the wires were connected to it went, the wires from the boiler can be identified from the diagram you posted below:

And the thermostat instructions

So, I think your description matches this, and yes the link should be removed. Although I assume you know this as you must have put it back to get the boiler running when you took out the Honeywell.

 

[Draughtsman]

The Riva was installed without the old Honeywell stat being wired in, hence the image with the link M still in place.

I bought the RTS 8 because the old Honeywell stat wasn't very good at low temps, it had to be set high or it wouldn't trigger the heating.

 

[stem]

Ah OK thanks for clarifying, the mention of the Honeywell was a red herring. Anyway, you're all sorted now.