The oven and all four hotplates light instantly.

But the grill on this gas cooker doesn't ignite properly.

The spark at the electrode looks fine; 5mm plus. New battery fitted.

There doesn't seem to be any blockage in the grill burner which looks
very clean.

Gas is getting to the burner. The electrode is down the far end of the
burner from the gas inlet.

If I turn the gas on full, then hold in the spark button and blow under
the grill the gas usually ignites.

But it refuses to ignite from the spark if I don't blow on it.

When it's burning the flames seem to come out of all the jets of the
burner.

The flames extend about 4-6" out of the jets.

This has me stumped. Any ideas?

On 31/01/2013 14:55, nick wrote:
The oven and all four hotplates light instantly.

But the grill on this gas cooker doesn't ignite properly.

The spark at the electrode looks fine; 5mm plus. New battery fitted.

There doesn't seem to be any blockage in the grill burner which looks
very clean.

Gas is getting to the burner. The electrode is down the far end of the
burner from the gas inlet.

If I turn the gas on full, then hold in the spark button and blow under
the grill the gas usually ignites.

But it refuses to ignite from the spark if I don't blow on it.

When it's burning the flames seem to come out of all the jets of the
burner.

The flames extend about 4-6" out of the jets.

This has me stumped. Any ideas?

This could just be a design flaw. Apart from that, take the burner out
and give it a good clean. Are the flames blue, btw?

On Thu, 31 Jan 2013 16:01:03 +0000, GB wrote:

This could just be a design flaw. Apart from that, take the burner out
and give it a good clean. Are the flames blue, btw?

There must be millions of these things out there; all with non-igniting
grills?

Took the burner out. Could be stainless steel. It is so clean it looks
like new. Doesn't look like the grill has ever been used. Now I know
why.

The flames are blue except at the tips where they are yellowish.

In article ,
nick writes:
On Thu, 31 Jan 2013 16:01:03 +0000, GB wrote:

This could just be a design flaw. Apart from that, take the burner out
and give it a good clean. Are the flames blue, btw?

There must be millions of these things out there; all with non-igniting
grills?

Took the burner out. Could be stainless steel. It is so clean it looks
like new. Doesn't look like the grill has ever been used. Now I know
why.

The flames are blue except at the tips where they are yellowish.

which suggests the air inlet at the jet is obstructed, but could
also be caused by dust further along the burner generating resistance
to the gas/aid flow, the back-pressure from which will reduce the
air drawn in alongside the jet. It's probably generating a little
more carbon monoxide than it would if operating cleanly.

You may need to clean the inside of the burner tube. Often a blast
with a compressed air can will do, but if there's a spider's nest
in there, you'll need something more substantial.

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

On 01/02/2013 16:50, Andrew Gabriel wrote:
In article ,
nick writes:
On Thu, 31 Jan 2013 16:01:03 +0000, GB wrote:

This could just be a design flaw. Apart from that, take the burner out
and give it a good clean. Are the flames blue, btw?

There must be millions of these things out there; all with non-igniting
grills?

Took the burner out. Could be stainless steel. It is so clean it looks
like new. Doesn't look like the grill has ever been used. Now I know
why.

The flames are blue except at the tips where they are yellowish.

shouldn't be any yellow


which suggests the air inlet at the jet is obstructed, but could
also be caused by dust further along the burner generating resistance
to the gas/aid flow, the back-pressure from which will reduce the
air drawn in alongside the jet. It's probably generating a little
more carbon monoxide than it would if operating cleanly.

You may need to clean the inside of the burner tube. Often a blast
with a compressed air can will do, but if there's a spider's nest
in there, you'll need something more substantial.

And check the jet where the gas is squirted into the burner.

By the way, to clean it, you can just run it under the tap.

On Thu, 31 Jan 2013 14:55:37 +0000 (UTC), nick wrote:

The spark at the electrode looks fine; 5mm plus. New battery fitted.

A long spark is a weak spark, the energy is going into breaking down lots
of air to make the arc rather than ionising more air on a shorter arc.

I'd check that whatever it is arcing to hasn't moved or erroded away,
same applies to the electrode. If all looks positioned OK I'd be tempted
to *gently* bend the electrode to make a spark say 3mm long.

--
Cheers
Dave.

On Thu, 31 Jan 2013 16:25:38 +0000, Dave Liquorice wrote:

On Thu, 31 Jan 2013 14:55:37 +0000 (UTC), nick wrote:

The spark at the electrode looks fine; 5mm plus. New battery fitted.

A long spark is a weak spark, the energy is going into breaking down
lots of air to make the arc rather than ionising more air on a shorter
arc.

I'd check that whatever it is arcing to hasn't moved or eroded away,
same applies to the electrode. If all looks positioned OK I'd be tempted
to *gently* bend the electrode to make a spark say 3mm long.

Point taken about the spark. But a longer spark has more chance of
passing through the gas?

But I'll try a shorter spark.

The electrode arcs to the lower edge of the burner. Right next to the
last jet on the burner.

On Fri, 1 Feb 2013 15:09:58 +0000 (UTC), nick wrote:

Point taken about the spark. But a longer spark has more chance of
passing through the gas?

But the further the gas is away from the burner jet the more dilute it
will be and possibly outside the required range for ignition...

--
Cheers
Dave.