Am replacing my rad valves with TRVs.

I was going to mount them vertically, the same as the existing
valves...however, before I do so is there any benefit (Either
operational or efficiency) to mounting them horizontally?

sponix

On Tue, 27 Sep 2005 08:42:29 GMT, (s--p--o--n--i--x) wrote:

Am replacing my rad valves with TRVs.

I was going to mount them vertically, the same as the existing
valves...however, before I do so is there any benefit (Either
operational or efficiency) to mounting them horizontally?

They are supposed to work more effectively in a horizontal position, as air
currents flow more freely past the sensor. However, I think they look naff
mounted that way, and (having kids) look all too tempting to stand on.

I have one rad with the TRV that way round (installers put it at the wrong
end and didn't notice until after the system was filled), and it is always
at a noticeable lower setting for the same room temp, so there is something
in that argument. But I find all the vertically-mounted ones behave
perfectly acceptably.

--
Thunder rolled. ... It rolled a six.

On Tue, 27 Sep 2005 10:47:54 +0100, John Laird
wrote:

On Tue, 27 Sep 2005 08:42:29 GMT, (s--p--o--n--i--x) wrote:

Am replacing my rad valves with TRVs.

One last question..

The new TRVs come with olives, compression nuts and a stub of pipe
that is threaded at one end.

The radiators are 35 years old and I don't think the old 'stubs' will
come out. Obviously removing the old olive I may damage the stub and
have to renew the stub.

If I re-use the old nut/olives/stub is it likely to leak? Is there an
easy way to remove the old stub of pipe?

sponix

"s--p--o--n--i--x" wrote in message

Is there an
easy way to remove the old stub of pipe?


Heat and stilsons

Regards Jeff

On Tue, 27 Sep 2005 10:30:54 GMT, (s--p--o--n--i--x)
scrawled:

The new TRVs come with olives, compression nuts and a stub of pipe
that is threaded at one end.

The radiators are 35 years old and I don't think the old 'stubs' will
come out. Obviously removing the old olive I may damage the stub and
have to renew the stub.

If I re-use the old nut/olives/stub is it likely to leak? Is there an
easy way to remove the old stub of pipe?

Shouldn't be any adverse affects from reusing the tails, they should
all be the same size. Just make sure you seal them properly when
you're reassembling.
--
Stuart @ SJW Electrical

Please Reply to group

On Tue, 27 Sep 2005 10:30:54 GMT, (s--p--o--n--i--x) wrote:

On Tue, 27 Sep 2005 10:47:54 +0100, John Laird
wrote:

On Tue, 27 Sep 2005 08:42:29 GMT, (s--p--o--n--i--x) wrote:

Am replacing my rad valves with TRVs.

One last question..

The new TRVs come with olives, compression nuts and a stub of pipe
that is threaded at one end.

The radiators are 35 years old and I don't think the old 'stubs' will
come out. Obviously removing the old olive I may damage the stub and
have to renew the stub.

If I re-use the old nut/olives/stub is it likely to leak? Is there an
easy way to remove the old stub of pipe?

The "stubs" are known as radiator tails. It's unlikely you will damage one
in the act of removing an olive, as the olive is much softer (the tail is a
lump of steel). Some tails are presented to the valve as a length of 15mm
(or 1/2", same size) pipe, and the join is made with a compression fitting
and an olive. If your existing tails look like this, and your valves have
15mm compression fittings on both ends, then you can use the old tails.
However, some valves and tails have a mating surface which looks like part
of a sphere. These must match, and will have been supplied together. If
your existing pipework has these, then you will need to replace the tails.
It should be easy to tell - the tightening nut is much larger than a normal
15mm compression one.

It's not usually that difficult to get tails out - I have had more trouble
getting a decent seal putting new ones in (they have a tapered thread). A
large hex wrench from the plumbing section of your local diy shed is the
usual tool - it should exactly match the new tails. It may or may not match
the old tails, or they might have internal splines which mesh with slots in
the wrench. I've sometimes had to jam a large screwdriver in alongside the
hex tool if the tail hole is too large. Put new ones in with PTFE tape, and
do them up *tight*.

I would get a move on though - the first real cold snap will always coincide
with a heating system disaster ime.

--
First shalt thou pull out the Holy Pin

w

Am replacing my rad valves with TRVs.

A comment I read here, which appears to make sense is that the TRV can be
placed in the return instead of the flow (if it's a biderectional one, and
I think they mostly are) on account of the return is 10 deg cooler, with a
bit of luck, and the lockshield goes in the flow; I'm giving it a whirl,
though I think, TBH, you just set the thingy to feel right, and it'll be ok
regardless

mike

On Tue, 27 Sep 2005 12:20:02 +0100, John Laird
wrote:

The "stubs" are known as radiator tails. It's unlikely you will damage one
in the act of removing an olive, as the olive is much softer (the tail is a
lump of steel). Some tails are presented to the valve as a length of 15mm
(or 1/2", same size) pipe, and the join is made with a compression fitting
and an olive. If your existing tails look like this, and your valves have
15mm compression fittings on both ends, then you can use the old tails.
However, some valves and tails have a mating surface which looks like part
of a sphere. These must match, and will have been supplied together. If
your existing pipework has these, then you will need to replace the tails.
It should be easy to tell - the tightening nut is much larger than a normal
15mm compression one.

It had crossed my mind that they might be like that..

It's not usually that difficult to get tails out - I have had more trouble
getting a decent seal putting new ones in (they have a tapered thread). A
large hex wrench from the plumbing section of your local diy shed is the
usual tool - it should exactly match the new tails. It may or may not match
the old tails, or they might have internal splines which mesh with slots in
the wrench. I've sometimes had to jam a large screwdriver in alongside the
hex tool if the tail hole is too large. Put new ones in with PTFE tape, and
do them up *tight*.

Do all tails have the same thread? As the rads are early 70s I'm
worried that there may have been an imperial-metric changeover at some
point in time.

I would get a move on though - the first real cold snap will always coincide
with a heating system disaster ime.

Shhhh! Don't tempt fate!

sponix

s--p--o--n--i--x wrote:
John Laird wrote:
The "stubs" are known as radiator tails. It's unlikely you will damage one
in the act of removing an olive, as the olive is much softer (the tail is a
lump of steel). Some tails are presented to the valve as a length of 15mm
(or 1/2", same size) pipe, and the join is made with a compression fitting
and an olive. If your existing tails look like this, and your valves have
15mm compression fittings on both ends, then you can use the old tails.
However, some valves and tails have a mating surface which looks like part
of a sphere. These must match, and will have been supplied together. If
your existing pipework has these, then you will need to replace the tails.
It should be easy to tell - the tightening nut is much larger than a normal
15mm compression one.


It had crossed my mind that they might be like that..

You need a big allen key to get them out (or rather
get them in, if need be you can apply stillsons to
extract them).

In an earlier contribution to this discussion,
s--p--o--n--i--x wrote:


Do all tails have the same thread? As the rads are early 70s I'm
worried that there may have been an imperial-metric changeover at some
point in time.

The threads will all be 1/2" BSP (British Standard Pipe) - which actually
has an OD of 0.825" (21mm) because it's the thread which would be on the
*outside* of an iron pipe with a nominal 1/2" bore.

Pipe threads have stayed the same over the past few decades even though
copper pipe sizes have gone metric.

The only thing to watch out for is that some old radiators have 3/4" BSP
(just over 1" in real money) threads - so they will have been fitted with
internally/externally threaded bushes to enable them to use 1/2" valves. If
your rads have got these, try not to disturb the bushes - hold the hex of
the bush with a wrench whilst you unscrew the valve tail from it.
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

On Tue, 27 Sep 2005 15:28:57 +0100, "Set Square"
wrote:

The only thing to watch out for is that some old radiators have 3/4" BSP
(just over 1" in real money) threads - so they will have been fitted with
internally/externally threaded bushes to enable them to use 1/2" valves. If
your rads have got these, try not to disturb the bushes - hold the hex of
the bush with a wrench whilst you unscrew the valve tail from it.

I never realised rads could be so much fun!

Thanks everyone who responded

sponix

On 27 Sep 2005 12:18:05 GMT, mike ring
wrote:

w

Am replacing my rad valves with TRVs.

A comment I read here, which appears to make sense is that the TRV can be
placed in the return instead of the flow (if it's a biderectional one, and
I think they mostly are) on account of the return is 10 deg cooler, with a
bit of luck, and the lockshield goes in the flow; I'm giving it a whirl,
though I think, TBH, you just set the thingy to feel right, and it'll be ok
regardless

I suppose if it is placed in the return then the TRV will be less
affected by the heat of the water flowing through it?

sponix

-

I suppose if it is placed in the return then the TRV will be less
affected by the heat of the water flowing through it?

Yes, that was the reason given here, not long ago, but I can't find it -
it's prolly deeply buried by now. The same sort of reasoning as mounting
them horizontally.

I doubt if it makes a ha'porth of difference, but once someone's suggested
a thing like that, I just *have to do it.

(Its a BOF thing)

mike

On 27 Sep 2005 21:56:31 GMT, mike ring
wrote:

I doubt if it makes a ha'porth of difference, but once someone's suggested
a thing like that, I just *have to do it.

Oooh! Perhaps you'd like to buy some new improved patented TRV heat
shields, from Sponix Industries?

Only £19.99 each and lovingly hand crafted from cat food can lids,
these shields fit simply to the TRV head using elastic bands (Not
supplied) and protect the TRV from the heat radiated by the radiator!

Endorsed by John Prescott! Buy now!

sponix

I doubt if it makes a ha'porth of difference, but once someone's
suggested a thing like that, I just *have to do it.

Oooh! Perhaps you'd like to buy some new improved patented TRV heat
shields, from Sponix Industries?

Only £19.99 each and lovingly hand crafted from cat food can lids,
these shields fit simply to the TRV head using elastic bands (Not
supplied) and protect the TRV from the heat radiated by the radiator!

Endorsed by John Prescott! Buy now!

sponix

LOL :-))

mike

In article ,
s--p--o--n--i--x wrote:
The radiators are 35 years old and I don't think the old 'stubs' will
come out. Obviously removing the old olive I may damage the stub and
have to renew the stub.

The 'stub' doesn't usually have a removable olive - it's part of the pipe.

But they're usually chrome plated, and if there's evidence of PTFE tape
should come out ok.

If I re-use the old nut/olives/stub is it likely to leak? Is there an
easy way to remove the old stub of pipe?

There's a hex inside it which an allen key fits.

--
*Gargling is a good way to see if your throat leaks.

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
(s--p--o--n--i--x) writes:

Endorsed by John Prescott! Buy now!

What does that look like, a large fist imprint?

--
Andrew Gabriel

In article ,
Andrew Gabriel andrew@a17 wrote:
Endorsed by John Prescott! Buy now!

What does that look like, a large fist imprint?

But he's probably got two 'combi's'

--
*Warning: Dates in Calendar are closer than they appear.

Dave Plowman London SW
To e-mail, change noise into sound.

On Wed, 28 Sep 2005 14:18:34 +0100, Dave Plowman (News) wrote:

In article ,
s--p--o--n--i--x wrote:
The radiators are 35 years old and I don't think the old 'stubs' will
come out. Obviously removing the old olive I may damage the stub and
have to renew the stub.

The 'stub' doesn't usually have a removable olive - it's part of the pipe.

But they're usually chrome plated, and if there's evidence of PTFE tape
should come out ok.

If I re-use the old nut/olives/stub is it likely to leak? Is there an
easy way to remove the old stub of pipe?

There's a hex inside it which an allen key fits.

sometimes they have square holes and others have round holes with two
'tits'. Screwfix part 11467 will fit all of them - usually.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html

On Thu, 29 Sep 2005 00:25:41 +0100, Ed Sirett
wrote:

..with two 'tits'.

Ah, we are back onto Prescott again..

sponix

On Wed, 28 Sep 2005 14:18:34 +0100, "Dave Plowman (News)"
wrote:

In article ,
s--p--o--n--i--x wrote:
The radiators are 35 years old and I don't think the old 'stubs' will
come out. Obviously removing the old olive I may damage the stub and
have to renew the stub.

The 'stub' doesn't usually have a removable olive - it's part of the pipe.

An olive on the valve end of the tail.

sponix