Nest Gen 3 to Worcester Greenstar combi 8000 Style

[Ronson63]

Existing - Boiler, Fused spur & fixed room stat ( 2 core low voltage

I am happy with the wiring, however, I would like to confirm the connection from heat link (Terminal 2) to LR (Radiator symbol) fig

 

[Ronson63]

Replace existing wall-mounted room thermostat (2 core cable in place)

Can I just confirm the Heat link terminal 2 is connected to LR (Rad Symbol) as per boiler manual

Heat Link Boiler Thermostat

L /N L/N 230 OUT
Term 1 L 230 OUT
Term 2 LR ???
T1 T1
T2 T2

 

[stem]

You've posted your enquiry twice and both are in the wrong forums, so have broken two of the forum rules in one go...but as you're a newbie here's the info you require

The mains supply you have right, and also the T1 & T2 connections.

For the Heatlink
No connection is made to terminal 1
Terminal 2 (Heating Common) link to Heatlink L
Terminal 3 (Heating call for Heat) goes to boiler LR (CH Live Return)

You don't mention an earth, but an earth is required to the earth terminal which is to the left of Heatlink terminals T1 & T2

 

[stem]

I've replied to your duplicate post in the 'Trade Talk' forum.

For future reference either the 'Plumbing & Central Heating' or 'Electrics UK' would have been a better place for your question as that's where the folks in the know about such things hang out.

If you look at the top of the forums you have used, they are described as:

DIY Disasters​

This forum is for posts about disasters you have experienced. General questions or queries should be posted in the appropriate forum section.

Trade Talk​

Talk for the trade to discuss trade related topics e.g. quotes, customer issues, etc. Do NOT place general queries here.

Edit
Ah, I see the mods have move it to the correct forum.

 

[Deleted member 317380]

Just for clarity, as it’s a bit confusing, the T1 and T2 only go from heat link to Nest thermostat for power supply and not on the T1 - 1/2 on the boiler terminal strip, as this is for weather compensation.

 

[stem]

I notice the OP hasn't been on the forum since he first posted his question.

So they won't have seen the replies. I've found it a few times before with others. I wonder why they don't check back. I can remember once spending about 30 minutes answering a detailed question and producing a diagram to assist, only for an OP never to see it.

 

[Deleted member 317380]

I notice the OP hasn't been on the forum since he first posted his question.

View attachment 350588

So they won't have seen the replies. I've found it a few times before with others. I wonder why they don't check back. I can remember once spending about 30 minutes answering a detailed question and producing a diagram to assist, only for an OP never to see it.

The mind boggles. Maybe they asked on another site and got the answer too?

 

[RandomGrinch]

There have been a few posts that I have really wanted to know the outcome of; especially when I've put a load of effort trying to work out wiring connections, when all we are presented with, is a picture of spaghetti!
It's possible that some of these posters do see the answers, but unlike us regulars, don't set an automatic log-in - all we would see is an anonymous view.

 

[ericmark]

Oh dear, I am 99% sure the BUS is NOT Low Voltage but in fact extra low voltage, so likely everything else shown as low voltage is also extra low voltage, this is not USA, we should abide by ISO rules.

As to suitable thermostats, clearly the best option is one which connects to the BUS, but any other thermostat must NOT have anti-hysteresis software as it will stop the boiler modulating correctly. Working, and working efficiently, are not the same, and the Nest thermostat is, as I found out to my cost, unable to work with any TRV heads or sensors, so it is really unsuitable for most homes with doors unless using hot air.