Hi All,

We are building a house with wet underfloor heating which goes back
to 2 control units, which have all the wiring completed, only leaving
2 wires from each unit going back to the boiler (volt free). the
boiler has now been installed (Worcester Greenstar 12/18) which I
could not find any volt free connections, I spoke with Worcester bosch
technical today and all they could tell me was that the boiler doesn`t
have the appropriate connections, but could not tell me how I could
resolve this problem.
Anyone shed any light???.

On Fri, 02 Jan 2009 10:55:10 -0800, yekal_tytwr wrote:

Hi All,

We are building a house with wet underfloor heating which goes back
to 2 control units, which have all the wiring completed, only leaving
2 wires from each unit going back to the boiler (volt free). the
boiler has now been installed (Worcester Greenstar 12/18)

Is that an oil boiler? I don't recognise the model name as a gas one.

... which I
could not find any volt free connections, I spoke with Worcester bosch
technical today and all they could tell me was that the boiler doesn`t
have the appropriate connections, but could not tell me how I could
resolve this problem.
Anyone shed any light???.

Not sure what your UFH control units require. You say they want volt-free
connections but not whether the connection is a signal from the boiler to
the UFH controller or the other way. If the former maybe the UFH
controller has its own mains power for its pump and just needs a contact
closure to tell it to run the pump. In that case I'd be thinking along
the lines of fitting a pipe thermostat to the boiler's flow pipe to tell
the UFH when there's heat coming from the boiler.

Alternatively if the volt-free connection is a signal /from/ the UFH
controller /to/ the boiler from a set of contacts in the controller, then
I'd think along the lines of connecting across the boiler's LS and LR
terminals.

I think you really need to scan and post the UFH instructions somewhere for
us all to see (or point us to the mfr's docs online).



--
John Stumbles -- http://yaph.co.uk

A: Because it messes up the order in which people read text.
Q: Why is top-posting a bad thing?

On Jan 2, 9:21*pm, YAPH wrote:
On Fri, 02 Jan 2009 10:55:10 -0800, yekal_tytwr wrote:
Hi All,

* *We are building a house with wet underfloor heating which goes back
to 2 control units, which have all the wiring completed, only leaving
2 wires from each unit going back to the boiler *(volt free). the
boiler has now been installed (Worcester Greenstar 12/18)

Is that an oil boiler? I don't recognise the model name as a gas one.


Yes this is an oil condensing boiler



... which I
could not find any volt free connections, I spoke with Worcester bosch
technical today and all they could tell me was that the boiler doesn`t
have the appropriate connections, but could not tell me how I could
resolve this problem.
* *Anyone shed any light???.

Not sure what your UFH control units require. You say they want volt-free
connections but not whether the connection is a signal from the boiler to
the UFH controller or the other way. If the former maybe the UFH
controller has its own mains power for its pump and just needs a contact
closure to tell it to run the pump. In that case I'd be thinking along
the lines of fitting a pipe thermostat to the boiler's flow pipe to tell
the UFH when there's heat coming from the boiler.

Alternatively if the volt-free connection is a signal /from/ the UFH
controller /to/ the boiler from a set of contacts in the controller, then
I'd think along the lines of connecting across the boiler's LS and LR
terminals.

I think you really need to scan and post the UFH instructions somewhere for
us all to see (or point us to the mfr's docs online).


thanks for your reply , I can`t work out if it is possible to post the
wiring diagrams on here, would you mind if I email them to you?.



--
John Stumbles *-- *http://yaph.co.uk

A: Because it messes up the order in which people read text.
Q: Why is top-posting a bad thing?

Yekal wrote:
On Jan 2, 9:21 pm, YAPH wrote:
On Fri, 02 Jan 2009 10:55:10 -0800, yekal_tytwr wrote:
Hi All,

We are building a house with wet underfloor heating which goes back
to 2 control units, which have all the wiring completed, only
leaving 2 wires from each unit going back to the boiler (volt
free). the boiler has now been installed (Worcester Greenstar 12/18)

Is that an oil boiler? I don't recognise the model name as a gas one.


Yes this is an oil condensing boiler



... which I
could not find any volt free connections, I spoke with Worcester
bosch technical today and all they could tell me was that the
boiler doesn`t have the appropriate connections, but could not tell
me how I could resolve this problem.
Anyone shed any light???.

Not sure what your UFH control units require. You say they want
volt-free connections but not whether the connection is a signal
from the boiler to the UFH controller or the other way. If the
former maybe the UFH controller has its own mains power for its pump
and just needs a contact closure to tell it to run the pump. In that
case I'd be thinking along
the lines of fitting a pipe thermostat to the boiler's flow pipe to
tell the UFH when there's heat coming from the boiler.

Alternatively if the volt-free connection is a signal /from/ the UFH
controller /to/ the boiler from a set of contacts in the controller,
then I'd think along the lines of connecting across the boiler's LS
and LR terminals.

I think you really need to scan and post the UFH instructions
somewhere for us all to see (or point us to the mfr's docs online).


thanks for your reply , I can`t work out if it is possible to post the
wiring diagrams on here, would you mind if I email them to you?.



--
John Stumbles -- http://yaph.co.uk

A: Because it messes up the order in which people read text.
Q: Why is top-posting a bad thing?

Scan - or photograph the picture[s] using a digital camera and upload them
to www.tinypic.com, give a 'Tag' (or name) and then post the IMG Code for
Forums & Message Boards link to the group. Example below (it works if you
want to view the image):

Note: leave out the [IMG]
either side and post link thus:

http://i44.tinypic.com/25gavxt.jpg - note the coloured and underlined text
that indicates a valid link.


Hope this helps


Cash

On Jan 2, 11:07*pm, "Cash"
wrote:
Yekal wrote:
On Jan 2, 9:21 pm, YAPH wrote:
On Fri, 02 Jan 2009 10:55:10 -0800, yekal_tytwr wrote:
Hi All,

We are building a house with wet underfloor heating which goes back
to 2 control units, which have all the wiring completed, only
leaving 2 wires from each unit going back to the boiler (volt
free). the boiler has now been installed (Worcester Greenstar 12/18)

Is that an oil boiler? I don't recognise the model name as a gas one.

*Yes this is an oil condensing boiler

... which I
could not find any volt free connections, I spoke with Worcester
bosch technical today and all they could tell me was that the
boiler doesn`t have the appropriate connections, but could not tell
me how I could resolve this problem.
Anyone shed any light???.

Not sure what your UFH control units require. You say they want
volt-free connections but not whether the connection is a signal
from the boiler to the UFH controller or the other way. If the
former maybe the UFH controller has its own mains power for its pump
and just needs a contact closure to tell it to run the pump. In that
case I'd be thinking along
the lines of fitting a pipe thermostat to the boiler's flow pipe to
tell the UFH when there's heat coming from the boiler.

Alternatively if the volt-free connection is a signal /from/ the UFH
controller /to/ the boiler from a set of contacts in the controller,
then I'd think along the lines of connecting across the boiler's LS
and LR terminals.

I think you really need to scan and post the UFH instructions
somewhere for us all to see (or point us to the mfr's docs online).

thanks for your reply , I can`t work out if it is possible to post the
wiring diagrams on here, would you *mind if I email them to you?.

--
John Stumbles --http://yaph.co.uk

A: Because it messes up the order in which people read text.
Q: Why is top-posting a bad thing?

Scan - or photograph the picture[s] using a digital camera and upload them
towww.tinypic.com, give a 'Tag' (or name) and then post the IMG Code for
Forums & Message Boards link to the group. *Example below (it works if you
want to view the image):

*Note: leave out the [IMG]
either side and post link thus:

http://i44.tinypic.com/25gavxt.jpg- note the coloured and underlined text
that indicates a valid link.

Hope this helps

Cash- Hide quoted text -

- Show quoted text -

Thanks for all that, I will give it a go fingers crossed!!

http://i40.tinypic.com/2eund40.jpg this one is the boiler wiring
diagram

http://i44.tinypic.com/303e4c7.jpg and this should be heating
diagram

this link has not gone blue as yours hopefully it will appear blue
when I post, well here we go!

On Sat, 03 Jan 2009 11:31:12 -0800, Yekal wrote:

http://i40.tinypic.com/2eund40.jpg this one is the boiler wiring
diagram

http://i44.tinypic.com/303e4c7.jpg and this should be heating
diagram

OK the "boiler relay / volt-free" connection is a pair of contacts which
close when the controller wants the boiler to run. It's "volt-free" because
neither of the contacts is tied to anything of a set voltage, such as
mains live. If you wire that pair of contacts to LR and LS (leaving NS
not connected to anything) then the boiler will fire up when the
controller wants it to. Assuming the boiler has a pump built-in then that
wil run too, without you having to connect anything to the boiler's "pump
relay / voltfree" contacts.



--
John Stumbles -- http://yaph.co.uk

Thank God I'm an atheist