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Drayton TRV4 reverse / reversible flow?

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David Robinson

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Oct 18, 2010, 5:29:22 AM10/18/10
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I may be mistaken, but I'm sure I've read on here that Drayton TRV4s
don't care about the direction of flow of water - i.e. they can be
fitted on flow or return, and don't care.

I've bought one to have a look, and this isn't what it says at all.
The one I bought said "reverse flow" - though all the ones I've seen
on-line seem to say this. You _can_ fit it to flow or return, but you
need to know which is which because on flow it needs to be mounted
vertically, and on return it needs to be mounted horizontally.

This makes sense. So, is there a version of the TRV4 which is truly
agnostic to the direction of flow? If not, can I fit these in the
wrong way without breaking them, and swap them around if they play up?
Because there are parts of the system where I think it would be far
easier and quicker to do this than to find out which is flow and
return before fitting them!

(system is completely in pieces now with no rads fitted, and some pipe
runs missing).

Cheers,
David.

Peter Scott

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Oct 18, 2010, 5:35:32 AM10/18/10
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If not, can I fit these in the
> wrong way without breaking them, and swap them around if they play up?
> Because there are parts of the system where I think it would be far
> easier and quicker to do this than to find out which is flow and
> return before fitting them!


If you don't mind draining the systemagain, why not try it? However, a
few years back I had a problem with loud rumbling or thundering where
similar valves had been fitted (not by me) the wrong way round.

Peter Scptt

Roger Mills

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Oct 18, 2010, 7:44:16 AM10/18/10
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TRV4s *are* agnostic to flow direction. Maybe they could have chosen a
better term, but that's what Drayton mean by "reverse flow". If you look
on the valve body, you will see a right-angled arrow with an arrow-head
on both ends, indicating that either direction of flow is ok.
--
Cheers,
Roger
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David Robinson

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Oct 18, 2010, 10:57:09 AM10/18/10
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It's true - I see that arrow - so why do the instructions (on the flap
of the box itself!) say otherwise?!

If the instructions were/are true, I think it means it's supposed to
work with the water pushing against the valve (i.e. pushing it open,
rather than shut).

(There's a funny symbol - something like pi, but not - under one end
of that arrow but not the other).

Cheers,
David.

Peter Andrews

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Oct 18, 2010, 1:02:03 PM10/18/10
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"David Robinson" <davidr...@postmaster.co.uk> wrote in message
news:778e0412-149e-4140...@l8g2000yql.googlegroups.com...
Older TR4's bodies were directional - although the heads are the same.

Peter


John

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Oct 18, 2010, 2:08:27 PM10/18/10
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"Peter Andrews" <p.an...@blueblueyonder.co.uk> wrote in message
news:g4%uo.2724$hw7....@newsfe10.ams2...

Mine have this as well. Any ideas?


Roger Mills

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Oct 18, 2010, 5:46:25 PM10/18/10
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On 18/10/2010 15:57, David Robinson wrote:
>
>
> It's true - I see that arrow - so why do the instructions (on the flap
> of the box itself!) say otherwise?!
>

What do the instructions *actually* say? Can you scan them, and upload
an image somewhere, with a link here?

David Robinson

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Oct 20, 2010, 6:18:35 AM10/20/10
to
On 18 Oct, 22:46, Roger Mills <watt.ty...@gmail.com> wrote:
> On 18/10/2010 15:57, David Robinson wrote:
>
>
>
> > It's true - I see that arrow - so why do the instructions (on the flap
> > of the box itself!) say otherwise?!
>
> What do the instructions *actually* say? Can you scan them, and upload
> an image somewhere, with a link here?

Will do.

They're _not_ the same as the ones on Drayton's website, which say
"15mm angle TRV4 bodies feature REVERSE FLOW capability enabling
installation on the flow or return, with the head either vertical or
horizontal."
Found in "TRV4 Thermostatic Radiator Valve Datasheet" from here:
http://www.draytoncontrols.co.uk/TRV4ThermostaticRadiatorValves.aspx

Cheers,
David.

John

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Oct 20, 2010, 8:30:09 AM10/20/10
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"David Robinson" <davidr...@postmaster.co.uk> wrote in message
news:9e417d22-8576-4fd9...@n26g2000yqh.googlegroups.com...

No info yet on the "Pi" symbol - I have BOSS valves and these have the
symbol (can be seen in some illustrations)
http://www.bssindustrial.co.uk/download/89/BOSS-Radiator-Valve-Range.pdf

I am wondering if it is merely a trade mark for the brass stamping.


Roger Mills

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Oct 20, 2010, 10:23:28 AM10/20/10
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On 20/10/2010 11:18, David Robinson wrote:

>
> They're _not_ the same as the ones on Drayton's website, which say
> "15mm angle TRV4 bodies feature REVERSE FLOW capability enabling
> installation on the flow or return, with the head either vertical or
> horizontal."
> Found in "TRV4 Thermostatic Radiator Valve Datasheet" from here:
> http://www.draytoncontrols.co.uk/TRV4ThermostaticRadiatorValves.aspx
>

I can't see anything in that which says they're anything other than
bi-directional. Can you?

David Robinson

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Oct 21, 2010, 8:26:34 AM10/21/10
to
On 20 Oct, 15:23, Roger Mills <watt.ty...@gmail.com> wrote:
> On 20/10/2010 11:18, David Robinson wrote:
>
>
>
> > They're _not_ the same as the ones on Drayton's website, which say
> > "15mm angle TRV4 bodies feature REVERSE FLOW capability enabling
> > installation on the flow or return, with the head either vertical or
> > horizontal."
> > Found in "TRV4 Thermostatic Radiator Valve Datasheet" from here:
> >http://www.draytoncontrols.co.uk/TRV4ThermostaticRadiatorValves.aspx
>
> I can't see anything in that which says they're anything other than
> bi-directional. Can you?

No, that was my point! Whereas mine say "15mm angled bodies can be
fitted vertically on the flow, or horizontally on the return" which
implies to me _ not_ horizontally on the flow, _nor_ vertically on the
return!

Anyway, I have uploaded photos as requested...

http://s633.photobucket.com/albums/uu59/2Bdecided/Drayton%20TRV4/?action=view&current=2.jpg

http://s633.photobucket.com/albums/uu59/2Bdecided/Drayton%20TRV4/

Isn't this exactly what all TRV4s look like??? At least, most of the
ones on eBay seem to look like this.

If so, why does the text apparently contradict what everyone knows to
be true? Or have 6 months hard DIY-ing wrecked my English
comprehension skills?! Or have I been sold a "fake"?!

Cheers,
David.

Roger Mills

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Oct 21, 2010, 11:17:41 AM10/21/10
to

That's very odd! That bit of text *does* suggest that they're
directional, whereas the "Reverse Flow" tag and the double-ended arrow
suggest that they're not!

I think you'd better contact Drayton - aka Invensys - in order to bottom
this out!

I'll be amazed if they *are* directional - but please us know what they say!

David Robinson

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Oct 21, 2010, 11:36:26 AM10/21/10
to
On 21 Oct, 16:17, Roger Mills <watt.ty...@gmail.com> wrote:
> On 21/10/2010 13:26, David Robinson wrote:
>
>
>
>
>
> > On 20 Oct, 15:23, Roger Mills<watt.ty...@gmail.com>  wrote:
> >> On 20/10/2010 11:18, David Robinson wrote:
>
> >>> They're _not_ the same as the ones on Drayton's website, which say
> >>> "15mm angle TRV4 bodies feature REVERSE FLOW capability enabling
> >>> installation on the flow or return, with the head either vertical or
> >>> horizontal."
> >>> Found in "TRV4 Thermostatic Radiator Valve Datasheet" from here:
> >>>http://www.draytoncontrols.co.uk/TRV4ThermostaticRadiatorValves.aspx
>
> >> I can't see anything in that which says they're anything other than
> >> bi-directional. Can you?
>
> > No, that was my point! Whereas mine say "15mm angled bodies can be
> > fitted vertically on the flow, or horizontally on the return" which
> > implies to me _ not_ horizontally on the flow, _nor_ vertically on the
> > return!
>
> > Anyway, I have uploaded photos as requested...
>
> >http://s633.photobucket.com/albums/uu59/2Bdecided/Drayton%20TRV4/?act...

>
> >http://s633.photobucket.com/albums/uu59/2Bdecided/Drayton%20TRV4/
>
> > Isn't this exactly what all TRV4s look like??? At least, most of the
> > ones on eBay seem to look like this.
>
> > If so, why does the text apparently contradict what everyone knows to
> > be true? Or have 6 months hard DIY-ing wrecked my English
> > comprehension skills?! Or have I been sold a "fake"?!
>
> > Cheers,
> > David.
>
> That's very odd! That bit of text *does* suggest that they're
> directional, whereas the "Reverse Flow" tag and the double-ended arrow
> suggest that they're not!
>
> I think you'd better contact Drayton - aka Invensys - in order to bottom
> this out!
>
> I'll be amazed if they *are* directional - but please us know what they say!

I'll feel an idiot phoning them, since their website is very clear...

http://www.draytoncontrols.co.uk/content.aspx?id=15322#TRV’s

...never the less, for the sake of figuring out why their packaging
says what it does, I phoned them, and...

"It's badly worded - use it either way around" was their response.

So I can stop worrying!

And you were all right all along. :-) But then I expect nothing less
from most folks here on uk.d-i-y!

Thanks again.

Cheers,
David.

Roger Mills

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Oct 21, 2010, 1:31:09 PM10/21/10
to
On 21/10/2010 16:36, David Robinson wrote:

>
> I'll feel an idiot phoning them, since their website is very clear...
>
> http://www.draytoncontrols.co.uk/content.aspx?id=15322#TRV’s
>
> ...never the less, for the sake of figuring out why their packaging
> says what it does, I phoned them, and...
>
> "It's badly worded - use it either way around" was their response.
>
> So I can stop worrying!
>
> And you were all right all along. :-) But then I expect nothing less
> from most folks here on uk.d-i-y!
>
> Thanks again.
>
> Cheers,
> David.

Good - glad that's sorted out!

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