Probably not a DIY topic but I think there will be folks out there who
have an opinion.

I need to move my gas fire to a new location as I'm rearranging the
room layout. I'm limited as to where a balanced flue can go, and unless
somebody has a good idea I don't think I will be able to use the
existing chimney. The chimney is a line of hollow bricks going up the
cavity wall ca 1980.

I've seen several models of flueless fires which claim to be 100%
efficient and deliver up to 3.5 KW, which would be adequate. I find it
hard to accept the idea of filling up the room with CO2 as being a good
thing, though I guess they must be approved and considered safe.

Comments anyone?

andyv wrote:
Probably not a DIY topic but I think there will be folks out there who
have an opinion.

I need to move my gas fire to a new location as I'm rearranging the
room layout. I'm limited as to where a balanced flue can go, and
unless somebody has a good idea I don't think I will be able to use
the existing chimney. The chimney is a line of hollow bricks going up
the cavity wall ca 1980.

I've seen several models of flueless fires which claim to be 100%
efficient and deliver up to 3.5 KW, which would be adequate. I find it
hard to accept the idea of filling up the room with CO2 as being a
good thing, though I guess they must be approved and considered safe.

Comments anyone?

They are safe given that they are fitted with a catalytic(sp?) converter,
similar to those in cars.
That said, I still wouldn't have one in a room without good ventilation, and
by good ventilation I mean an unobstructed 9 inch by 6 inch permanent vent
(not a sliding louvre type), overkill yes, but I doubt if it would be
noticable with the heat that flueless fires give out.

andyv wrote:
Probably not a DIY topic but I think there will be folks out there who
have an opinion.

I need to move my gas fire to a new location as I'm rearranging the
room layout. I'm limited as to where a balanced flue can go, and unless
somebody has a good idea I don't think I will be able to use the
existing chimney. The chimney is a line of hollow bricks going up the
cavity wall ca 1980.

I've seen several models of flueless fires which claim to be 100%
efficient and deliver up to 3.5 KW, which would be adequate. I find it
hard to accept the idea of filling up the room with CO2 as being a good
thing, though I guess they must be approved and considered safe.

Comments anyone?

The catalytic converters should deal with any CO that's produced -
that's the real nasty stuff. I guess the CO2 would be no different to a
gas hob running.....

andyv wrote:
Probably not a DIY topic but I think there will be folks out there who
have an opinion.

I need to move my gas fire to a new location as I'm rearranging the
room layout. I'm limited as to where a balanced flue can go, and unless
somebody has a good idea I don't think I will be able to use the
existing chimney. The chimney is a line of hollow bricks going up the
cavity wall ca 1980.

I've seen several models of flueless fires which claim to be 100%
efficient and deliver up to 3.5 KW, which would be adequate. I find it
hard to accept the idea of filling up the room with CO2 as being a good
thing, though I guess they must be approved and considered safe.

Comments anyone?

ventilation, i would be in agreement with phil on the overkill vent!,
obviously you will have a window in the room that opens too.

out of interest i would like a look at the manufacturers installation
instructions if you do go ahead and fit one of these, just to find out
if there is yet a 'common' way of installing/venting/room size etc

I'm still undecided, but it's an interesting comment about gas cookers
as these usually vent straight into the kitchen. Not everybody has an
extractor.

A regular gas fire, such as I now have also probably vents some of its
exhaust into the room too.

The news groups are fine for getting some ideas about this, but I'd be
astounded if the installation notes for these appliances didn't exactly
specify the minimum ventilation requirements, probably in relation to
the size of the room they're installed in.

andyv wrote:

I'm still undecided, but it's an interesting comment about gas cookers
as these usually vent straight into the kitchen. Not everybody has an
extractor.

yes, but only for limited time. Running one all day is not smart. I
wouldnt install an unvented fire myself. They arent as safe as vented,
but more to the point youre breathing in the fumes day in day out. I've
been to a few places with old ones installed and cant say I liked the
atmosphere too much. They will also deposit a fair amount of damp of
course. I think you could do better.


NT

OK I think I have a viable idea. See what you think.

The existing fire has a chimney which runs up the cavity wall into the
loft. Here it runs in a concrete pipe and exhausts out through a vent
in the apex of the roof.

What if I was to fit an extractor fan into the piped section in the
loft? I could then have the room downstairs turning over the air and
sucking out the excess CO2 just as if it was going out of the window or
a conventional vent in the wall. I'd have a grating on the wall hidden
behind furniture. I don't fancy an extractor fan in the room itself
unless anybody can point me to an ultra quiet one.

Also it may even be possible to get a switch which operates when the
gas is flowing so the fan is automatically turned on.

andyv wrote:
OK I think I have a viable idea. See what you think.

The existing fire has a chimney which runs up the cavity wall into the
loft. Here it runs in a concrete pipe and exhausts out through a vent
in the apex of the roof.

What if I was to fit an extractor fan into the piped section in the
loft? I could then have the room downstairs turning over the air and
sucking out the excess CO2 just as if it was going out of the window
or a conventional vent in the wall. I'd have a grating on the wall
hidden behind furniture. I don't fancy an extractor fan in the room
itself unless anybody can point me to an ultra quiet one.

Also it may even be possible to get a switch which operates when the
gas is flowing so the fan is automatically turned on.

If you install a vent in the living room wall, and leave the existing flue
open, you can do away with the extractor fan altogether as the air will
naturally flow up the chimney (it will even without a vent, hold a lit match
in front of it if you don't believe me!)
The manufacturers insist on their safety as do British standards and gods
knows what other governing bodies, but when push comes to shove, the waste
products from that fire are going to end up in that room at some stage in
whatever form and over a long period of time, I can't see how this is going
to be benificial to either the room or it's occupants.
You'll find that a permanent vented room as mentioned above will make it a
lot more comfortable, and dryer too considering the water produced by
burning gas.

OK I just found a government report on this at
http://www.hse.gov.uk/research/rrpdf/rr023.pdf

Basically what it says is that when they had several of these fires
tested, they ended up with CO2 in excess of permitted occupational
exposure levels. These were admittedly tested at extreme conditions but
it doesn't fill me with much confidence..

andyv wrote:
OK I just found a government report on this at
http://www.hse.gov.uk/research/rrpdf/rr023.pdf

Basically what it says is that when they had several of these fires
tested, they ended up with CO2 in excess of permitted occupational
exposure levels. These were admittedly tested at extreme conditions
but it doesn't fill me with much confidence..

CO2 isn't toxic.
It's when there is no oxygen left in the room that the fire takes in the CO2
and produces CO - carbon monoxide.
With good ventilation this can never happen, although breathing in CO2 isn't
much fun, it won't kill you outright.
As you say, the testing conditions would probably *never* occur in real
life - how many rooms are completely sealed and air tight?
A few vents, probably one in each side if it's possible for cross-flow
ventilation, although not imperative would certainly make it more
comfortable.

On Mon, 10 Apr 2006 14:22:23 GMT, "Phil L"
wrote:

|andyv wrote:
| OK I just found a government report on this at
| http://www.hse.gov.uk/research/rrpdf/rr023.pdf
|
| Basically what it says is that when they had several of these fires
| tested, they ended up with CO2 in excess of permitted occupational
| exposure levels. These were admittedly tested at extreme conditions
| but it doesn't fill me with much confidence..
|
|CO2 isn't toxic.

Not strictly true.
http://en.wikipedia.org/wiki/Carbon_dioxide

When inhaled in high concentrations (about 5% by volume), it is toxic to
humans and other animals. This is sometimes known as choke damp, an old
mining industry term, and was the cause of death at Lake Nyos in Cameroon,
where an upwelling of CO2-laden lake water in 1986 covered a wide area in a
blanket of the gas, killing nearly 2000..


|It's when there is no oxygen left in the room that the fire takes in the CO2
|and produces CO - carbon monoxide.

See above:

--
Dave Fawthrop dave hyphenologist co uk Google Groups is IME the *worst*
method of accessing usenet. GG subscribers would be well advised get a
newsreader, say Agent, and a newsserver, say news.individual.net. These
will allow them: to see only *new* posts, a killfile, and other goodies.

Dave Fawthrop wrote:
"Phil L" wrote:
|andyv wrote:
| OK I just found a government report on this at
| http://www.hse.gov.uk/research/rrpdf/rr023.pdf
|
| Basically what it says is that when they had several of these fires
| tested, they ended up with CO2 in excess of permitted occupational
| exposure levels. These were admittedly tested at extreme conditions
| but it doesn't fill me with much confidence..
|
|CO2 isn't toxic.

Not strictly true.
http://en.wikipedia.org/wiki/Carbon_dioxide

It is true, CO2 is non-toxic. To say it is toxic is like saying
that water is toxic because you can drown in it.


|It's when there is no oxygen left in the room that the fire takes in the CO2
|and produces CO - carbon monoxide.

Shorely shome mishtake here. If there's no oxygen in the room,
the fire will go out. CO2 doesn't burn.

Chris Bacon wrote:
Dave Fawthrop wrote:
"Phil L" wrote:
andyv wrote:
OK I just found a government report on this at
http://www.hse.gov.uk/research/rrpdf/rr023.pdf

Basically what it says is that when they had several of these fires
tested, they ended up with CO2 in excess of permitted occupational
exposure levels. These were admittedly tested at extreme conditions
but it doesn't fill me with much confidence..

CO2 isn't toxic.

Not strictly true.
http://en.wikipedia.org/wiki/Carbon_dioxide

It is true, CO2 is non-toxic. To say it is toxic is like saying
that water is toxic because you can drown in it.

Correct, carbon dioxide is in our lungs nearly all the time, given that we
inhale oxygen and exhale carbon dioxide.


It's when there is no oxygen left in the room that the fire takes
in the CO2 and produces CO - carbon monoxide.

Shorely shome mishtake here. If there's no oxygen in the room,
the fire will go out. CO2 doesn't burn.

There's always /some/ oxygen in the room, it's just that high concentrations
of CO2 cause the hydrocarbons in the gas to not burn properly, when this
occurs the gas produces CO instead of CO2....it doesn't actually *turn* CO2
into CO, but CO2 does cause the production of CO, given that it's presence
is in place of oxygen.

On Mon, 10 Apr 2006 16:48:46 +0100, Chris Bacon
wrote:

|Dave Fawthrop wrote:
| "Phil L" wrote:
| |andyv wrote:
| | OK I just found a government report on this at
| | http://www.hse.gov.uk/research/rrpdf/rr023.pdf
| |
| | Basically what it says is that when they had several of these fires
| | tested, they ended up with CO2 in excess of permitted occupational
| | exposure levels. These were admittedly tested at extreme conditions
| | but it doesn't fill me with much confidence..
| |
| |CO2 isn't toxic.
|
| Not strictly true.
| http://en.wikipedia.org/wiki/Carbon_dioxide
|
|It is true, CO2 is non-toxic. To say it is toxic is like saying
|that water is toxic because you can drown in it.

If you read what you snipped 5% CO2 is lethal which leaves about 15%
oxygen http://en.wikipedia.org/wiki/Air

If you took the trouble to read the rest of
http://en.wikipedia.org/wiki/Carbon_dioxide and followed the internal
links, you would find the reason in great detail.
..
--
Dave Fawthrop dave hyphenologist co uk Google Groups is IME the *worst*
method of accessing usenet. GG subscribers would be well advised get a
newsreader, say Agent, and a newsserver, say news.individual.net. These
will allow them: to see only *new* posts, a killfile, and other goodies.

Dave Fawthrop wrote:
On Mon, 10 Apr 2006 14:22:23 GMT, "Phil L"
wrote:
|andyv wrote:

| OK I just found a government report on this at
| http://www.hse.gov.uk/research/rrpdf/rr023.pdf
|
| Basically what it says is that when they had several of these fires
| tested, they ended up with CO2 in excess of permitted occupational
| exposure levels. These were admittedly tested at extreme conditions
| but it doesn't fill me with much confidence..
|
|CO2 isn't toxic.

Not strictly true.
http://en.wikipedia.org/wiki/Carbon_dioxide

When inhaled in high concentrations (about 5% by volume), it is toxic to
humans and other animals. This is sometimes known as choke damp, an old
mining industry term, and was the cause of death at Lake Nyos in Cameroon,
where an upwelling of CO2-laden lake water in 1986 covered a wide area in a
blanket of the gas, killing nearly 2000..

Next question is at what level does it have some effect on health. I
dont know.


NT

Dave Fawthrop wrote:
Chris Bacon wrote:

|Dave Fawthrop wrote:
| "Phil L" wrote:
| |andyv wrote:
| | OK I just found a government report on this at
| | http://www.hse.gov.uk/research/rrpdf/rr023.pdf
| |
| | Basically what it says is that when they had several of these fires
| | tested, they ended up with CO2 in excess of permitted occupational
| | exposure levels. These were admittedly tested at extreme conditions
| | but it doesn't fill me with much confidence..
| |
| |CO2 isn't toxic.
|
| Not strictly true.
| http://en.wikipedia.org/wiki/Carbon_dioxide
|
|It is true, CO2 is non-toxic. To say it is toxic is like saying
|that water is toxic because you can drown in it.

If you read what you snipped 5% CO2 is lethal which leaves about 15%
oxygen http://en.wikipedia.org/wiki/Air

If you took the trouble to read the rest of
http://en.wikipedia.org/wiki/Carbon_dioxide and followed the internal
links, you would find the reason in great detail.
.

So water is toxic, too. Whatever you want.

On Tue, 11 Apr 2006 10:15:25 +0100, Chris Bacon
wrote:

|Dave Fawthrop wrote:
| Chris Bacon wrote:
|
| |Dave Fawthrop wrote:
| | "Phil L" wrote:
| | |andyv wrote:
| | | OK I just found a government report on this at
| | | http://www.hse.gov.uk/research/rrpdf/rr023.pdf
| | |
| | | Basically what it says is that when they had several of these fires
| | | tested, they ended up with CO2 in excess of permitted occupational
| | | exposure levels. These were admittedly tested at extreme conditions
| | | but it doesn't fill me with much confidence..
| | |
| | |CO2 isn't toxic.
| |
| | Not strictly true.
| | http://en.wikipedia.org/wiki/Carbon_dioxide
| |
| |It is true, CO2 is non-toxic. To say it is toxic is like saying
| |that water is toxic because you can drown in it.
|
| If you read what you snipped 5% CO2 is lethal which leaves about 15%
| oxygen http://en.wikipedia.org/wiki/Air
|
| If you took the trouble to read the rest of
| http://en.wikipedia.org/wiki/Carbon_dioxide and followed the internal
| links, you would find the reason in great detail.
| .
|
|So water is toxic, too.

In huge quantities taken by mouth, Yes.

|Whatever you want.

Not me Wikipedia, or Google will get you lots of other URLs saying the same
things.
--
Dave Fawthrop dave hyphenologist co uk Google Groups is IME the *worst*
method of accessing usenet. GG subscribers would be well advised get a
newsreader, say Agent, and a newsserver, say news.individual.net. These
will allow them: to see only *new* posts, a killfile, and other goodies.

Chris Bacon wrote:
Dave Fawthrop wrote:
Chris Bacon wrote:

|Dave Fawthrop wrote:
| "Phil L" wrote:
| |andyv wrote:
| | OK I just found a government report on this at
| | http://www.hse.gov.uk/research/rrpdf/rr023.pdf
| |
| | Basically what it says is that when they had several of these fires
| | tested, they ended up with CO2 in excess of permitted occupational
| | exposure levels. These were admittedly tested at extreme conditions
| | but it doesn't fill me with much confidence..
| |
| |CO2 isn't toxic.
|
| Not strictly true.
| http://en.wikipedia.org/wiki/Carbon_dioxide
|
|It is true, CO2 is non-toxic. To say it is toxic is like saying
|that water is toxic because you can drown in it.

If you read what you snipped 5% CO2 is lethal which leaves about 15%
oxygen http://en.wikipedia.org/wiki/Air

If you took the trouble to read the rest of
http://en.wikipedia.org/wiki/Carbon_dioxide and followed the internal
links, you would find the reason in great detail.
.

So water is toxic, too. Whatever you want.

Not really. Trying to breath a mixture of 15% oxygen, 5% helium (or
some other inert gas), and 80% nitrogen will be fine. Replace the 5%
helium with 5% CO2, and you will be fine.

Of course, CO2 is a lot less toxic than many gasses, but it isn't
entirely non-toxic.

Dave Fawthrop wrote:

Not me Wikipedia, or Google will get you lots of other URLs saying
the same things.

CO2 isn't toxic inthat it will kill you by poisoning, it may kill you via
the non-presence of oxygen but it's not toxic like carbon monoxide, I think
this is all getting pedantic now anyway, we breath carbon dioxide every day
from our birth to our deaths, if it was poisonous we wouldn't live very
long.
Carbon monoxide is poisonous and worse still it has cumulative effects,
meaning that levels of it can build up in the bloodstream for weeks, months
or even years unnoticed until one day it reaches the point where it causes
death.

On Tue, 11 Apr 2006 16:22:54 GMT, "Phil L"
wrote:

|Dave Fawthrop wrote:
|
| Not me Wikipedia, or Google will get you lots of other URLs saying
| the same things.
|
|CO2 isn't toxic inthat it will kill you by poisoning, it may kill you via
|the non-presence of oxygen but it's not toxic like carbon monoxide, I think
|this is all getting pedantic now anyway, we breath carbon dioxide every day
|from our birth to our deaths, if it was poisonous we wouldn't live very
|long.

Some people should learn to use Google, and read what they find

http://en.wikipedia.org/wiki/Carbon_dioxide

Carbon dioxide content in fresh air is approximately 0.04%, and in exhaled
air approximately 4.5%. When inhaled in high concentrations (about 5% by
volume),

***it is toxic to humans and other animals.***

This is sometimes known as choke damp, an old mining industry term, and was
the cause of death at Lake Nyos in Cameroon, where an upwelling of
CO2-laden lake water in 1986 covered a wide area in a blanket of the gas,
killing nearly 2000.

Hemoglobin, the main oxygen-carrying molecule in red blood cells, can carry
both oxygen and carbon dioxide, although in quite different ways. The
decreased binding to oxygen in the blood due to increased carbon dioxide
levels is known as the Haldane Effect, and is important in the transport of
carbon dioxide from the tissues to the lungs. Conversely, a rise in the
partial pressure of CO2 or a lower pH will cause offloading of oxygen from
hemoglobin. This is known as the Bohr Effect.

--
Dave Fawthrop dave hyphenologist co uk Google Groups is IME the *worst*
method of accessing usenet. GG subscribers would be well advised get a
newsreader, say Agent, and a newsserver, say news.individual.net. These
will allow them: to see only *new* posts, a killfile, and other goodies.

Dave Fawthrop wrote:
"Phil L" wrote:
|Dave Fawthrop wrote:
| Not me Wikipedia, or Google will get you lots of other URLs saying
| the same things.
|
|CO2 isn't toxic inthat it will kill you by poisoning, it may kill you via
|the non-presence of oxygen but it's not toxic like carbon monoxide

Some people should learn to use Google, and read what they find

http://en.wikipedia.org/wiki/Carbon_dioxide

Hell's bells. *Still* running wide. Try these:

http://tinyurl.com/fmqzb


































http://www.woodlandsltd.com/acatalog...inkers_45.html

Dave Fawthrop wrote:
On Tue, 11 Apr 2006 16:22:54 GMT, "Phil L"
wrote:

Dave Fawthrop wrote:

Not me Wikipedia, or Google will get you lots of other URLs saying
the same things.

CO2 isn't toxic inthat it will kill you by poisoning, it may kill
you via the non-presence of oxygen but it's not toxic like carbon
monoxide, I think this is all getting pedantic now anyway, we breath
carbon dioxide every day from our birth to our deaths, if it was
poisonous we wouldn't live very long.

Some people should learn to use Google, and read what they find

http://en.wikipedia.org/wiki/Carbon_dioxide

what part of 'this is all getting pedantic now' did you not grasp? - the Op
doesn't live in a dissused mine in outer mongolia, he lives in a house, the
CO2 levels cannot get that high under these circumstances otherwise how
would anyone *ever* die of monoxide poisoning?

I don't know why you are seeking glory with this, you are just making
yourself look foolish....AFWIW, Wiki is written by anyone, I could go and
edit any page right now to prove any point I like, primary schoolkids know
that we breath CO2 every day and it's not toxic, if it was there wouldn't be
any need for primary schools because we wouldn't be here.

primary schoolkids know that we breath CO2 every day and it's not
toxic, if it was there wouldn't be any need for primary schools
because we wouldn't be here.

The problem is not pedanticism. The problem is that the statement "CO2 is
not toxic" is false. It is toxic. It is not displacement of oxygen that
causes this toxicity. It is only toxic in concentrations that are unlikely
to occur in a domestic setting.

You call being correct pedantic. However, others can't allow such a false
statement to continue unchallenged.

Christian.

Christian McArdle wrote:
primary schoolkids know that we breath CO2 every day and it's not
toxic, if it was there wouldn't be any need for primary schools
because we wouldn't be here.

The problem is not pedanticism. The problem is that the statement
"CO2 is not toxic" is false. It is toxic. It is not displacement of
oxygen that causes this toxicity.

Toxic means it poisons you, so if we all have it around us all the time, how
do we manage to live for 70 years?
- why does it not kill us slowly like lead or other elements?


It is only toxic in concentrations
that are unlikely to occur in a domestic setting.

Which is what we were talking about....and the pedantics started creeping in
around here.


You call being correct pedantic. However, others can't allow such a
false statement to continue unchallenged.

Because they're being pedantic...everything is toxic *given the right
volumes and concentrations* - it was obvious to anyone with even half a
degree of common sense that it was to this room, with the unvented gas fire
inside it that I was referring, unless I'm expected to end each sentence
with, "in the context of this room, with the unvented gas fire inside it"

On Wed, 12 Apr 2006 16:38:35 +0000, Phil L wrote:

Christian McArdle wrote:
primary schoolkids know that we breath CO2 every day and it's not
toxic, if it was there wouldn't be any need for primary schools
because we wouldn't be here.

The problem is not pedanticism. The problem is that the statement
"CO2 is not toxic" is false. It is toxic. It is not displacement of
oxygen that causes this toxicity.

Toxic means it poisons you, so if we all have it around us all the time, how
do we manage to live for 70 years?
- why does it not kill us slowly like lead or other elements?


AIUI there are at least two aspect to toxicity. How much (or what
concentration) will kill you in a given short time. How much can you be
exposed to regularly and have no long term ill effects.

I believe that CO2 needs something around 15% plus in air to kill you in
hours. (IIRC the concentrations in Apollo 13 got over 10% before they
managed to get the LiOH filters working.)

Clearly exposure values of less than 0.5% are both unavoidable and
inconsequential.

I'm informed that 4000ppm of CO is fatal in minutes. The safe exposure
limit is 50ppm.

AIUI even water has a toxicity (IIRC something like 10 litres in less than
60minutes is fatal).

--
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
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html

Ed Sirett wrote:
On Wed, 12 Apr 2006 16:38:35 +0000, Phil L wrote:

Christian McArdle wrote:
primary schoolkids know that we breath CO2 every day and it's not
toxic, if it was there wouldn't be any need for primary schools
because we wouldn't be here.

The problem is not pedanticism. The problem is that the statement
"CO2 is not toxic" is false. It is toxic. It is not displacement of
oxygen that causes this toxicity.

Toxic means it poisons you, so if we all have it around us all the
time, how do we manage to live for 70 years?
- why does it not kill us slowly like lead or other elements?


AIUI there are at least two aspect to toxicity. How much (or what
concentration) will kill you in a given short time. How much can you
be exposed to regularly and have no long term ill effects.

I believe that CO2 needs something around 15% plus in air to kill you
in hours. (IIRC the concentrations in Apollo 13 got over 10% before
they managed to get the LiOH filters working.)

Clearly exposure values of less than 0.5% are both unavoidable and
inconsequential.

I'm informed that 4000ppm of CO is fatal in minutes. The safe exposure
limit is 50ppm.

AIUI even water has a toxicity (IIRC something like 10 litres in less
than 60minutes is fatal).

So there's no possibility of carbon dioxide killing people in a domestic
house, with an unvented gas fire? - pretty much what I said.
Even the tests on them have proven that it doesn't get anywehere close to
the 'permitted levels' boundary.