Gas fire one radiant burns yellow

[H. Neary]

Hi
Fitted a replacement gas fire yesterday. It wasn't new and had
been stored for over a year.

One radiant seems to burn with a yellow flame compared to the rest. I
switched the gas jet and radiant itself but there is no difference.

The gasflow is simple, a four holed jet to feed ach radiant a space
[not adjustable] of around 15mm then a tube around 10mmwide by 30mm
length that ends in a fine grid under the radiant.

Any thoughts on the subject would be very welcome

HN

[Andrew Gabriel]

In article <4gapl71s8g21jrlgt...@4ax.com>,

A picture would help, but it sounds like it's not mixing air
in with the gas. This is normally done immediately after the
jet, which points into a tube with openings at/near the jet
to draw air in. Something around there isn't working right,
most commonly dust or debris in the air intake or mixing
tube.

It's not safe to operate until it's been cleaned/serviced
(and not just the one obviously faulty one, but the whole thing).
The yellow flame means it's not burning properly, and could
be giving off carbon monoxide and soot.
Also need to check the flue, and that the ventilation in the
room meets the manufacturer's installation instructions.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

[js.b1]

On Mar 11, 2:51 pm, and...@cucumber.demon.co.uk (Andrew Gabriel)
wrote:

> It's not safe to operate until it's been cleaned/serviced
> (and not just the one obviously faulty one, but the whole thing).
> The yellow flame means it's not burning properly, and could
> be giving off carbon monoxide and soot.
> Also need to check the flue, and that the ventilation in the
> room meets the manufacturer's installation instructions.

Gas fires rely on a fresh air duct to the burners, the duct usually
runs from the knob end.

When the heat settings are 2-burners or 2+2-burners there is a duplex
duct.

The most heavily used setting is often Low/Medium, which means that
duct tend to get clogged with dust - particularly in a carpeted
environment re long-hairs. In which case the burner with flicker
yellow, burn yellow, and also burn tall. Heat output usually sucks (so
it is wasting money), it is producing a lot of CO (as all gas fires
do), and it is clogging the chimney with soot which will regularly
fall down as marbles, is hygroscopic & pretty nasty to the mortar.

This is why in the old days, the proper gas fitters used to take them
outside and soak the burner/ducts in a paraffin wallpaper paste tank.
Those fitters are now usually Grid workers and occasionally will
service a gas fire properly for someone, fed up with the common
skimping.

If the radiants are broken, they are often not available. Missing
sections at the rear of radiants can cause local hot spotting of the
heat exchanger, which lets your CO producing appliance put PoC & CO
into the room. This is why a gas fire absolutely should have a working
CO alarm (and preferably a paper backup) in the room. Some like them
also upstairs re buggered flue - as well as in the loft.

Check the heat exchanger at the back for distortion and cracks, quite
a few units (Valor junk) tended to split the metal because it was too
thin when run too much on High. It was the decline of the gas fire re
cost v backstreet manufacturing practices.

[The Natural Philosopher]

probably traces of some metallic salt somewhere..or soot.

> HN
>


--
To people who know nothing, anything is possible.
To people who know too much, it is a sad fact
that they know how little is really possible -
and how hard it is to achieve it.

[H. Neary]

On Sun, 11 Mar 2012 17:25:30 +0000, The Natural Philosopher
<t...@invalid.invalid> wrote:

Many thanks for the help.

I do seem to recollect from school chemistry is was lack of air that
made Bunsen's yellow.

Anyway I had a look at the offending tube. A spider must have set up
home at some stage.

Thank's, I never thought to look inside the pipe. A gas air mix didn't
strike me as being the right medium to cause an obstruction!!


One lives & learns!


HN