Wiring 2nd Generation Nest Heat Link to Baxi Duo-Tec 28 HE a

[Stephen Crawford]

Hi all,

I think this is be a fairly simple job but just want to make sure I'm doing what I think I should before I go ahead with it.

I need to install a wireless Nest thermostat (so not connected directly to the boiler).

I have a Baxi Duo-Tec 28 HE a combi.

Currently I have a Salus wireless thermostat connected to a RF boiler control that's already wired to the boiler.

I've taken some pictures of how the RF control is wired at the moment and it's manual.



Is it just a case of me removing the RF and wiring the Heat Link to the same terminals the RF was wired to?

eg. from the RF to the Heat Link (HL):

RF (1) to HL (N)
RF (2) to HL (L)
RF (3) to HL (2)
RF (4) to HL (3)

Thanks for your help.

Steve

 

[stem]

Yep. That is correct.

 

[Stephen Crawford]

Great, thanks for your confirmation Stem.

The one other question I have would be that the RF wire is plugged into boiler via a kind of molex female plug. I was thinking to strip the wire at the other end and use a terminal box to wire it (if I can't find any spare molex plugs I can use) what amp terminal box should I use?

Thanks again.

 

[stem]

The boiler control circuits have minimal current draw, in fact the whole central heating system including the pump and boiler should only have a 3A fuse fitted, so you won't need anything very big. Most are rated at least 5A anyway.

 

[v6scorpion]

sorry to hijack this thread, but i have the same boiler and i have just bought salus rt500rf. The boiler had this thermostat downstairs hard wired https://w3.siemens.co.uk/buildingte...-controls/documentation/Documents/raa02_i.pdf, ive changed over the old dial setting bit at the front of the boiler and i think its synced but boiler isnt switching on, original wiring in boiler has this https://www.diynot.com/diy/threads/...iring-headache-doesnt-turn-heating-on.473134/ thanks

 

[stem]

sorry to hijack this thread

Then don't hijack it, start your own. See forum rule 6. You will be more likely to have it seen by others if you do, rather than tagging it on an old thread.

From the boiler picture you have referred to, which I have copied below, and as it was posted by someone else, I assume you have linked to for illustrative purposes and is not actually your boiler. The top two terminals shown with the yellow link are the ones you are interested in. If still present, the link should be removed, and one of the terminals connected to the Salus RT500RF 'NO' terminal and the other to the Salus 'COM' terminal



Then the Salus receiver also needs a Live and Neutral supply, this should be connected to the L & N supplied from the same fused connection unit as the boiler.

 

[v6scorpion]

There isnt anyway of wiring the thermostat to the no terminal and com as you can see from back of the salus. As for the reciever i have replaced the old dial bit like for like wiring. Them 2 top wires are there from the old hard wired to the thermostat so the link isnt there now.

 

[stem]

There isnt anyway of wiring the thermostat to the no terminal and com as you can see from back of the salus.

Correct, the Salus thermostat is battery operated and doesn't need any wires. The wring goes to the Salus Receiver, as I have described for you, and the thermostat communicates with the receiver by RF.

As for the reciever i have replaced the old dial bit like for like wiring. Them 2 top wires are there from the old hard wired to the thermostat so the link isnt there now.

Sorry I don't understand any of that, (other than the link isn't there, which is as it should be) How many wires were connected to the original thermostat, where were they connected to at the thermostat and what was each connected to at the other end of the cable?

 

[v6scorpion]

Its solved, ive replaced the original link wire boiler end.

 

[stem]

That is unlikely to solve it, it will probably just mean that the heating is now permanently 'on' The link is only fitted when there aren't any external controls fitted.

 

[AGAS]

Its solved, ive replaced the original link wire boiler end.

well shouldn't have bothered getting the stat then , at least you won't be cold . your own photos will go a long way

 

[v6scorpion]

I have this salus and no wire can go in the thermostat that goes in hallway, ive wired the receiver as the instructions say but it dont say how to do the bit where wire link was or is?
http://www.bhl.co.uk/salus-rt500bc-programmable-room-thermostat-with-rf-boiler-receiver.html

 

[AGAS]

I have this salus and no wire can go in the thermostat that goes in hallway, ive wired the receiver as the instructions say but it dont say how to do the bit where wire link was or is?

its all in the instructions , and again photo's would be good then appropriate help can be given

 

[stem]

Regarding the boiler and Salus RECEIVER, this is what you should end up with.



If you still have problems decommissioning the existing timer, then.....

photo's would be good then appropriate help can be given

 

[v6scorpion]

Thank you