Third Generation Nest Heat Link installation to a Vaillant Ecotec Pro 30

All,

I know there are a lot of threads on this forum, on a number of other forums and also videos on YouTube but I have found little information on this specific install and the information I have found has been confusing and sometimes contradictory.

I have just had a Vaillant Ecotec Pro 30 installed a couple of days ago and have only now just received our third generation NEST.

I have read the instruction manual and researched for a good few hours now on the net to find out how to connect the HeatLink to the boiler.



I have read Vaillant and NEST threads that say follow the 230V Combi boiler page above and also read threads that say follow the Dry Contact page (otherwise you'll fry your boiler PCB).

Hence I am confused!

There seems to be more posts suggesting the following connections (230V Combi page):

Boiler 3 (Live) to Heatlink L and 2 (Loop wire from L to 2)
Boiler 4 to Heatlink 3
Boiler 5 (Neutral) to Heatlink N

Could someone who has fitted a HeatLink to this boiler or an equivalent Vaillant offer up some further guidance?

Many thanks in advance!

Daz

 

It may depend on the variant you have. You have a choice of mains thermostat OR 24V dry contact control.

According to the manual there is a mains thermostat connection RT available on the TURQUOISE X1 block. This would connect to Heatlink 3, with Boiler L to Heatlink L and 2.Boiler L and N are also on the turquoise X1 block)

If you connect a 230 V AC time and temperature control to the boiler, then remove the bridge at input 24 V = RT (X100 or X106) if a bridge exists.

Removing the front cover of the boiler may compromise the room seal of the boiler and may be regulated by the Gas Safety (Installation and Use) Regulations. It may be illegal and dangerous for you to carry out this work. This post is not an encouragement for an unqualified person to carry out work on a gas appliance.

https://www.vaillant.co.uk/downloads/ecotec-pro-instn-maint-261423.pdf

 

Thanks for your reply!!
Only you've confused me even more now lol

What do you mean by the variant I have?
It's a NEST third generation thermostat and a Vaillant Ecotec Pro 30.

It's the NEST heatlink I need to connect.

 

Variant of boiler. Does your boiler have the connections show in that manual and as described?

If so then simplest is to follow the 230V combi boiler diagram abive and connect to the Turquoise X1 block in the boiler, and remove the link on the 24V-RT terminals on the X100 or X106 terminals on the boiler.

 

Thanks again for your reply!

The manual link is slightly different to the printer manual I have but look similar. I've photo'd the relevant pages or of my manual below. I'd appreciate any confirmation you can give before I go wiring anything up.





Many thanks!!

 

It's the same, see the bottom right text "connecting 230 volt controller", connect the Heatlink 3 terminal to RT next to the mains LNE connector and remove any link on X100 connector (circled (10) on the upper right list of things on the diagranm.

Removing the front cover of the boiler may compromise the room seal of the boiler and may be regulated by the Gas Safety (Installation and Use) Regulations. It may be illegal and dangerous for you to carry out this work. This post is not an encouragement for an unqualified person to carry out work on a gas appliance.

 

Many thanks for your help!!

All now working!!

 

But what the DIYer should have told you, is that a DIYer should not be opening the boiler as the case forms the room sealed part of the design which makes it so safe.

Until a DIYer opens it up that is!

 

Nest/ Hive 5

 

The DIYer didn't need to tell me this, as this DIYer already knew. So, yes it's worth highlighting, however despite the fact, I knew the stance and still wanted to fit it myself. For the competent DIYer there are now too many prohibitive rules in place for minor jobs. I am more than capable of connecting three wires, especially when the guy who came to fit the boiler said he had never fitted a NEST before. Whilst, yes it would be at his liability; it is also at my cost.

So, yes it is right to point it out. There are lots of things the DIYer "shouldn't" do and that's upto the individual if he wants to go ahead and ignore the rules. There's been too many occasions over the years where I've had to correct a "so-called" professional.

 

But you have demonstrated your lack of understanding of the risks.

It is not connecting the wires!

It is that the safety of the boiler depends on the case being air sealed to prevent combustion products entering the room.

Without realising the DIYer has infringed site rules which prevent giving advice on gas work ( which includes opening a room sealed case ).

Tony

 

I apologise if I have contravened forum rules. I would not advocate anyone doing anything which was not safe and within their competence. I did not get the impression from reading the boiler manual that removing the front cover would compromise the room sealing of the boiler and would be work that could only be carried out by a competent person under the Gas Regs. I think it's a pretty poor design of boiler if that is in fact the case. I have amended my post in case it comes up in a search engine in isolation.

 

The Vaillant Manual is very careful to state on the front cover "For the competent person"

If that was insufficient it says inside:-


1.4 Related documents


Installation and maintenance of the boiler


must only be performed by a competent person


with valid accreditation from the Health


and Safety Executive in accordance with the


"Gas Safety (Installation and Use) Regulations


1998" (hereinafter abbreviated to "competent


person" or "heating specialist company").

The existing regulations, rules and

guidelines must be observed when doing so.

Any special requirements of Local Authorities,

gas undertakings or insurers must be

complied with. The competent person is also

responsible for inspection, maintenance and

repairs to the boiler, and for checking gas

volume setting and flue gas analysis.


I don't think that is could be put much more clearly!

Tony

 

You've made your point numerous times now. Noted. Thank you.


Thank you again to OwainDIYer.

 

These types of controls are increasingly popular (judging by the number of enquiries on here about fitting the things) and yet there don't seem to be any warnings that one might have to be Gas Safe to fit them -- which depends on the exact type of boiler as on many boilers it would be possible to fit the control without being Gas Safe registered.

Oh well, I'm off to break the law again and do some unregistered electrical work.