Wiring and plumbing for UFH with a Vaillant ecotec combi boiler

[Sam11]

Hello all
(apologies in advance for first time post to this - or any forum for that matter!).
I have looked at similar posts but have not found anything addressing my issue exactly.

I have a Vaillant ecotec 828, a single zone wet ufh with manifold/mixer, a heatmiser rf switch and heatmiser touch programmable thermostat.

My plumber has plumbed in the manifold and fitted two motorised valves - one to the central heating feed from the boiler and one one to the ufh feed from the boiler.

The wiring centre has been fitted and the wireless programmer/thermostat communicates with it. The heatmiser touch is able to control 2 channels (HW and CH) but currently set to run 1 channel (CH ) only.

The radiators are controlled by a clock fitted in the boiler and TRV's - there is no room thermostat.

The wiring centre which has the following terminals: HW- CO2 NC2 NO2, CH - COM1 NC1 NO1, Boiler - LS LR, and - N E L

I have attached diagrams for the RF switch and the boiler.

I wish to do the following:

1. Able to have the UFH off and run the radiators only, and vice versa
2. The UFH and CH should only run the boiler when their timer is on/the UFH thermostat needs heat.
3. The UFH and CH should be able to turn the boiler off and on independently

I would very much appreciate if somebody could please provide some advice I can pass on to the plumber and the electrician on how to wire the two motorised valves with boiler/wiring centre to allow the separate control we are hoping for.
Thanks!

 

[Steelmasons]

CH zone valve will be opened via room stat (in your case clock/no interlock) which in turn will switch boiler via MV end switch.
UFH pump (circulator) will be switched via MV brown core which in turn will switch boiler via MV end switch.
Not rocket science...It says a lot for the 'plumber/electrician' when the client has to trawl the Internet in order to explain how to carry out the controls wiring........which I don't believe for a minute as I guess you are carrying out these works yourself..good luck..
A relay could be used in order to eliminate any voltage back feed should the circulators be fed via MV end switches although I would imagine this would just confuse the issue so carry on as above.

 

[Sam11]

Hello Steelmasons
Thanks for your speedy reply. Unfortunately I am not doing this myself but am having to be heavily involved as you can see.
Can you or anyone else have any specific help regarding my setup explained above?
I have read somewhere that it may be better to stop using the timeclock fitted to the boiler but instead use the heatmiser 2 channel switch to control CH and UFH (one on each channel). There was also mention of feeding both MV orange wires to the same terminal in the boiler. Unfortunately I cant find the forum/post where I saw this.

If anyone can help, would be much appreciated.
Thanks

 

[dilalio]

I have read somewhere that it may be better to stop using the timeclock

I'd stop using your plumber & electrician!
Whilst you are indeed in need of help, it's not really a DIY issue is it!
Do your tradesmen not know anyone with better knowledge they can consult, at their cost?
When I have something that is out of my knowledge zone, I have a number of associates I can call upon - it's part of a network I have built over years!

 

[Sam11]

Thanks for your advice dilalio.
Regarding your question, I believe they do and they are consulting but I want to do my own consulting too.
Anyway, I hope someone can help with my query.

 

[Steelmasons]

There was also mention of feeding both MV orange wires to the same terminal in the boiler. Unfortunately I cant find the forum/post where I saw this.

If anyone can help, would be much appreciated.
Thanks

Standard precedure to use MV end switch (orange core) to trigger boiler.

 

[Dan Robinson]

Imagine what would happen if they had a difficult installation to do .

 

[Dan Robinson]

Possibly the same muppets that left me with this bundle of joy to sort out?

 

[Sam11]

What a nightmare! Did you manage to sort it out?

 

[Dan Robinson]

Yeah - 2 hours to pull it all out and rewire it as it was supposed to be done. A prime example of @dilalio 's point - if you are beyond your natural limit, don't make the customer suffer. Stop and get someone in who can. Don't plough on and leave a non-functioning (and in my example) bloody dangerous installation.

 

[Sam11]

yeh well I'll see what ideas they come back with tomorrow - and decide if they know what they doing - before its touched - hence i needed to know how it should be done.

 

[Sam11]

Dan - is there a specific 'speciality' I need to look for eg heating engineer who could do what want - I mean plumber doesn't know enough and electrician doesn't know enough (although to be conformed tomorrow) - what type of tradesman do I need to get in to do the connections as I described above?

 

[picasso]

Where abouts in the country are you ? someone on here might be able to help.

 

[Sam11]

I'm in Cardiff

 

[Dan Robinson]

Dan - is there a specific 'speciality' I need to look for eg heating engineer who could do what want - I mean plumber doesn't know enough and electrician doesn't know enough (although to be conformed tomorrow) - what type of tradesman do I need to get in to do the connections as I described above?

A heating engineer/plumber should be able to wire his own systems IMHO. I wouldn't dream of letting someone else (especially a Sparky) go anywhere near one of my systems unless there was further home automation that needed integrating.

Just ask whoever is tendering the work if they can wire UFH systems or "S plan +". In reality though, it is just a glorified sequence of switches.