Unvented Heating System

[Craig Norman]

hi there to everyone, this is my first post and desperately looking for support to get my heating installation complete. I have build my own home and had all my heating installed but the wiring up of the system is something I cannot get sorted. With a mechanical and electrical engineering background I’m 95% of the way there but have a couple of questions.

Basically I have a valliant system and I am using a VS66 control box. To mix things up I have Nest thermostates to control the ground floor underfloor heating and another to control the upstairs radiators.

Firstly I have a question around the 2 way valves. My installer put two in but I think I need a third for the UFH?

Secondly the 2 way valves quite rightly have a switch feed but the V66 control box doesn’t allow for this only L, N, E. Not sure what to do with these?

Finally connecting up the call for heating on the Nest Thermostates, does anyone have any input on how these would connect to the Valliant V66 control box?

I have attached a simple diagram of the system. Would be great luck for anyone’s help. Thanks.

 

[Spoon]

Welcome to the forum mate.
I get confused easily... (I am a bear of very little brain, and long words bother me)
Why did the installer not wire up the system?
If he was not meant to then why did the installer not supply wiring diagrams for the install?

 

[Craig Norman]

Lets just say that we fell out so the final wiring didn't get done.....

 

[Craig Norman]

Also he fitted a 5 core Honeywell 2-way valve but have read that the Valiant control box only need the live and neutral but guessing if I just put this on permanent loop?

 

[Spoon]

Lets just say that we fell out so the final wiring didn't get done.....

mmmmm... would love to hear the other side of this story....
That's the problem with the internet, The guy could be a real muppet so you sacked him off or you would be trying something on so he walked... We will never know.
Did he not describe how it was going to work then you hired him?

 

[Craig Norman]

Don't get me wrong the guy did a great job of the plumbing, but was very vague in his electrical knowledge saying it will be ok once we get to that point. Similarly he left a few loose ends which took weeks to get him back to sort out. He was a good recommendation from someone I have worked with before, none the less I couldn't put up with the constant delays so had to let him go less the retention. Unfortunately there is a lot of work out there and many trades these days want to get in and get out to get to the next. The last 10% is always the hardest.


Yes, I full described what was needed and he re-laid back what was needed and how. I can see he has done a good job. The underfloor heating was install later so just the tails were left for connecting up. I can clearly understand what was installed, it is the finer detail on the connections and the relationships between them.


Unfortunately I cannot find any wiring schematic that really provides the solution to what I have. Valliant are not exactly open with linking their manuals together between products and NEST well as less than helpful. Hence why I got to this point…..

 

[Spoon]

Thanks for the explanation mate.
As you have built your own home, can't you get the electrician in who did work/testing in your home to come and do the job? It sound like you want to do the work.

 

[Craig Norman]

I have to be honest, there is not many electricians that want to touch heating systems, which I found strange. Similarly I struggle to understand the chargers to connect a couple of cables. Ideally I would like to do this myself and work it out just need some guidance. Otherwise its going to be trial and error.

 

[Taylortwocities]

I have to be honest, there is not many electricians that want to touch heating systems, which I found strange.

Its an attitude of mind. As a lad I spent all my spare time messing around with lamps and batteries and relays. When I left school I was a telephone apprentice then telecoms engineer. After several decades larking around with data comms stuff I left to become an electrician.

So my experience is working through the logic of all those lovely relay systems, which is just a load of switches really.
(Don't get me started on make before break contacts, and slugged coils).
Its the same with heating systems. I really love those little jobs with an air-source heat pump, system boiler, Megaflo tank, underfloor heating with 15 manifolds and 6 zones. Yum yum, gimmie more - this installation is gonna look like the Starship Enterprise.......

But if you not used to it, even a simple S plan looks scary.

 

[Spoon]

...Similarly I struggle to understand the chargers to connect a couple of cables. Ideally I would like to do this myself and work it out just need some guidance. Otherwise its going to be trial and error.

Unfortunately mate it's not that simple.. The design of the circuit has to be done to regs. Then tested when complete.
Do you know the regs for the circuit?
Do you have test equipment to test it afterwards?
Why not get a couple of quotes to see how much it would cost.

 

[Octopus]

I have to be honest, there is not many electricians that want to touch heating systems, which I found strange. Similarly I struggle to understand the charges to connect a couple of cables.

Lots of sparks enjoy doing heating systems

As for charges .................. hum so you want US to provide free of charge advice ....... sorry to dissappoint you but not from me or many others on here.

Sounds like a bit of a lash up to start with.

 

[Taylortwocities]

Sounds like a bit of a lash up to start with.

I regret that I agree. And especially with an unvented vessel. This requires exacting electrical safeguards. Installers must hold an Unvented Hot Water Systems certificate (G3).

Under Building Regulations, it is necessary to notify Local Authority Building Control (LABC) of the installation of both unvented and vented hot water cylinders.

Still want to DIY this?

 

[Spoon]

Still want to DIY this?

But all he needs to do is "connect a couple of cables"...

 

[Octopus]

So the OP has been back on and not updated us with their thoughts .............. as yet.

 

[buzzlightyear]

Lets just say that we fell out so the final wiring didn't get done

more like did not get paid!

 

[Leesparkykent]

Why would you bother with the V66 if your using nest to control the HW, CH and UFH? Seems like a waste of money. You would be best getting rid of it, as they're carp. All you need is a 2port for each zone, 2 heat links and a Honeywell junction box.

 

[Craig Norman]

Hilarious reply’s, never said that I was not prepared to pay. As for a lash up I have to agree I had a rogue trader and he got paid most of it, but that isn’t this issue. Looking for advice verses banta chat. Thought I would be in the right place to get some help.

Fully aware of the regs to it signed off, just looking for solutions. What I didn’t mention that most of the wiring is complete, hence the comment “only a couple of wires”. I did get a couple of quotes and they wanted £240 sheets to install just the Nests...I’m in the wrong business.

Never mind will leave this post here and will keep looking for some Sparks that can sort the complete thing out.

 

[Leesparkykent]

Hilarious reply’s, never said that I was not prepared to pay. As for a lash up I have to agree I had a rogue trader and he got paid most of it, but that isn’t this issue. Looking for advice verses banta chat. Thought I would be in the right place to get some help.

Fully aware of the regs to it signed off, just looking for solutions. What I didn’t mention that most of the wiring is complete, hence the comment “only a couple of wires”. I did get a couple of quotes and they wanted £240 sheets to install just the Nests...I’m in the wrong business.

Never mind will leave this post here and will keep looking for some Sparks that can sort the complete thing out.

£240 seems reasonable.

 

[buzzlightyear]

the op can look at the forums directory and pick up a spark near to him .