Where is the best place to position radiators. I have always
maintained it is on internal walls, because then the heat energy
actually heats the air in the room before going out of the window, and
you don't throw half of it out of the window before it does any good.

Am I right?

And does the correct answer change depending on climate?

Cheers,

John

On 1 May, 22:43, John Nagelson wrote:
Where is the best place to position radiators. I have always
maintained it is on internal walls, because then the heat energy
actually heats the air in the room before going out of the window, and
you don't throw half of it out of the window before it does any good.

Am I right?

And does the correct answer change depending on climate?

Cheers,

John

The slightly counter-intuitive theory is that it's better under the
window. Otherwise you tend to get a much greater temperature gradient
across the room - around the rad will be nice and cosy, by the window
will be icy.

Cheers!

Martin

On 1 May 2007 14:50:29 -0700, Martin Pentreath
wrote:

On 1 May, 22:43, John Nagelson wrote:
Where is the best place to position radiators. I have always
maintained it is on internal walls, because then the heat energy
actually heats the air in the room before going out of the window, and
you don't throw half of it out of the window before it does any good.

Am I right?

And does the correct answer change depending on climate?

Cheers,

John

The slightly counter-intuitive theory is that it's better under the
window. Otherwise you tend to get a much greater temperature gradient
across the room - around the rad will be nice and cosy, by the window
will be icy.

Cheers!

Martin

I've heard it said that the rad under the window stops the draft...
Well if you tuck the curtains in behind the rad maybe it does.

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Or get it delivered for free

On May 2, 12:13 am, Mogga wrote:
On 1 May 2007 14:50:29 -0700, Martin Pentreath

wrote:
On 1 May, wrote:
Where is the best place to position radiators. I have always
maintained it is on internal walls, because then the heat energy
actually heats the air in the room before going out of the window, and
you don't throw half of it out of the window before it does any good.

Am I right?

And does the correct answer change depending on climate?

Cheers,

John

The slightly counter-intuitive theory is that it's better under the
window. Otherwise you tend to get a much greater temperature gradient
across the room - around the rad will be nice and cosy, by the window
will be icy.

Cheers!

Martin

I've heard it said that the rad under the window stops the draft...
Well if you tuck the curtains in behind the rad maybe it does.

My windows don't have a noticeable draught from the outside (I live in
Lapland, so if they did, I'd be in trouble for most of the year), so I
guess this refers to the downdraught caused by convection, with the
cold air from above being sucked down and heated up, rather than just
whizzing across the floor, still being cold before it reaches a
radiator on the internal wall. But I've never been convinced by this
argument, because if you position radiators on internal walls you can
afford to turn them up higher and leave them on longer purely because
you are not chucking a large proportion of their heat straight out of
the window (or up behind the curtains). There is usually a fair amount
of air circulation in a room, people are opening and closing doors,
moving about, etc., so it's not as if all the warm air concentrates by
the ceiling to let the downdraught at the window and external wall
have its dastardly way with everyone's feet. Also the internal walls
act as storage heaters during the night.

Other people's experiences may differ, but I have always noticed a big
difference with coal and wood fires too, according to whether their
chimneys are on internal walls or external ones, with rooms heating up
much better (faster and warmer - I can't say I've noticed much
difference in terms of gradients) in the former case.

John

Martin Pentreath wrote:
On 1 May, 22:43, John Nagelson wrote:
Where is the best place to position radiators. I have always
maintained it is on internal walls, because then the heat energy
actually heats the air in the room before going out of the window, and
you don't throw half of it out of the window before it does any good.

Am I right?

And does the correct answer change depending on climate?

Cheers,

John

The slightly counter-intuitive theory is that it's better under the
window. Otherwise you tend to get a much greater temperature gradient
across the room - around the rad will be nice and cosy, by the window
will be icy.

I would think that with double glazing the effect is much less of an
issue than without, too... I daresay that if all windows had been double
glazed when central heating first came along, the habit of positioning
radiators in this way would never have happened.

David

On Wed, 02 May 2007 06:45:49 GMT, Lobster
wrote:

|!Martin Pentreath wrote:
|! On 1 May, 22:43, John Nagelson wrote:
|! Where is the best place to position radiators. I have always
|! maintained it is on internal walls, because then the heat energy
|! actually heats the air in the room before going out of the window, and
|! you don't throw half of it out of the window before it does any good.
|!
|! Am I right?
|!
|! And does the correct answer change depending on climate?
|!
|! Cheers,
|!
|! John
|!
|! The slightly counter-intuitive theory is that it's better under the
|! window. Otherwise you tend to get a much greater temperature gradient
|! across the room - around the rad will be nice and cosy, by the window
|! will be icy.
|!
|!I would think that with double glazing the effect is much less of an
|!issue than without, too... I daresay that if all windows had been double
|!glazed when central heating first came along, the habit of positioning
|!radiators in this way would never have happened.

Also in the bad old days, walls would also not be insulated as they are
now, so IMO it is still worth putting radiators under windows because they
still let more heat out of the room than any other common feature, causing
draughts.
--
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http://www.gutenberg.org/wiki/Main_Page Completely Free to any
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On May 2, 8:52 am, Dave Fawthrop
wrote:
On Wed, 02 May 2007 06:45:49 GMT, Lobster
wrote:

|!Martin Pentreath wrote:

|! On 1 May, wrote:
....

Also in the bad old days, walls would also not be insulated as they are
now, so IMO it is still worth putting radiators under windows because they
still let more heat out of the room than any other common feature, causing
draughts.

They do, but the heat energy in the room comes from the radiator, so
you might as well let it heat the house before it goes out of the
window, which it will do anyway (second law of thermodynamics).

One thing you can say about putting radiators under windows is that
they heat the air outside the windows better. Perhaps there is an
argument that this is a desirable thing in cold climates such as where
I live (where every winter there are some days when it's minus 30)?
Maybe it means less condensation or chance of windows icing up? (I
doubt this very strongly, but it's what some local people say who
favour putting radiators under windows. In England, the usual argument
from non-engineers has to do with memories of single-glazed poor-
quality windows, I think, before most people had central heating at
all. It is odd really, because most chimneys aren't near outside
walls).

I have been in older houses with curved radiators under bay windows
(!) that simply don't heat the rooms at all, even if they themselves
are handburningly hot to the touch.

John

"Lobster" wrote in message
...
Martin Pentreath wrote:
On 1 May, 22:43, John Nagelson wrote:
Where is the best place to position radiators. I have always
maintained it is on internal walls, because then the heat energy
actually heats the air in the room before going out of the
window, and
you don't throw half of it out of the window before it does any
good.

Am I right?

And does the correct answer change depending on climate?

Cheers,

John

The slightly counter-intuitive theory is that it's better under
the
window. Otherwise you tend to get a much greater temperature
gradient
across the room - around the rad will be nice and cosy, by the
window
will be icy.

I would think that with double glazing the effect is much less of an
issue than without, too... I daresay that if all windows had been
double
glazed when central heating first came along, the habit of
positioning
radiators in this way would never have happened.

David

Often siting under windows is the only realistic way of keeping enough
wall uncluttered for furniture in a small room, so there are other
considerations than just the heat loss.

AWEM

"John Nagelson" wrote in message
ps.com...
Where is the best place to position radiators. I have always
maintained it is on internal walls, because then the heat energy
actually heats the air in the room before going out of the window, and
you don't throw half of it out of the window before it does any good.

Am I right?

And does the correct answer change depending on climate?
I am sure I read you get better air circulation effect, thus better room
heating with a radiator positioned under a window, which is why its done. I
have a faint memory that if against a wall the hot air just rises up the
wall to the ceiling where as under a window the hot air disperses into the
room more.

On Tue, 01 May 2007 14:43:13 -0700, John Nagelson wrote:

Where is the best place to position radiators. I have always
maintained it is on internal walls, because then the heat energy
actually heats the air in the room before going out of the window, and
you don't throw half of it out of the window before it does any good.

Discussed here

http://wiki.diyfaq.org.uk/index.php?...sign#Locations