Problem with SMEG gas hob - seeking advice

manofthefora

I have a worktop SMEG gas hob Model SER34AX1 Type P6LN2x.

It has four burners. The largest is front left.

This has taken to producing a large variable flame that licks out from under the surface of say a frying pan or large saucepan.

The gas jets emerge from a unit which has multiple holes around the periphery and at the centre part. See attached images.

I have checked that all the holes are clear and I have soaked it in soapy water as suggested by SMEG for cleaning.

Is the unit just warn out? It looks fine!!

SMEG 1.jpg

SMEG 2.jpg

Any suggestions or comments appreciated please.

MOTF

Esel

I know you said the holes are clear, but make sure all of them are completely open and clear. Use a suitably-sized nail or similar (held in a pliers) to ream them out if necessary. Look through each hole against a source of light to check.

What colour is the flame where it flares out?

Eta: Not an expert, just my 2c worth! 😀

manofthefora

Yes, I did clear out the various holes - there are literally hundreds, of varying sizes.

But perhaps I was too gentle. I'll attack with more aggressive reaming screws and report back.

Thanks for your suggestion.

The flames are mostly blue in colour with some orange. Why do you ask that?

MOTF

Esel

The flames are mostly blue in colour with some orange. Why do you ask that?

My experience, with lots of carbon deposits in the holes, was a yellow flame/flare.

I think that pots boiling over could be a factor in carbon build-up.

manofthefora

Looks like you may be correct.

I worked on some of the holes and there is definitely a (small) improvement.

However it's VERY hard work finding nails of the correct size and holding then in a pliers. The various layers of holes vary in size.

Normal tapered reaming tools don't (I think) come in such small sizes.

MOTF

The Continental Op

Have you tried putting the flame spreader in a dish washer?

If I was cleaning it by hand I'd find a suitable size drill, and hold it in a pin vice - https://www.amazon.co.uk/Precision-Drilling-0-6-3mm-0-1-1mm-Electronic/dp/B092QT4QNB might have the right size?

The drill bits for a Dremel type tool might also be small enough, bits https://www.amazon.co.uk/Silverline-Tools-944740-Micro-Silver/dp/B01N3C6STL/

Then another option I'd try is blasting the holes with compressed air from an air line - do you know anyone with a compressor.

What gas are you using, bottled, propane, butane or natural gas? If its a bottle then perhaps think about changing the regulator the do fail after a while. I'd even change the bottle just to check.

manofthefora

Thanks for those comments. I did get some suitable sized drill bits and cleared out ALL the various holes.

Zero improvement. The gas is natural gas from Bord Gais!!

I am due a visit from a gas boiler installer next week and will ask for his opinion.

MOTF

Esel

Could there be crud in the pipe/ aperture on the hob feeding the spreader?

10-10-20

I'm thinking that the center part of the burner is warped as the very center of the burner appears to have a flow around it where it shouldn't. Rotate that burner a third of the way around and relight it in each of the three positions and see if the excessive gas flow follows a point in the burner.

Alun

I'm not sure if the burner can be rotated round 1/3. There's a locating key on the base which may lock it in one position, but we haven't got a photo of the underside of the burner to confirm.

Anyhow, the burner itself, apart from the holes being possibly blocked, looks pretty dirty with lots of burnt on crud so it wouldn't surprise me if the underside of it is equally dirty. What could be happening is that as a result of some crud on the bottom the burner isn't sitting cleanly on the base and gas is escaping around the edges.

If it was me I'd be getting a wire brush, or a wire brush in a drill, and cleaning the burner up big time paying special attention to the interface between the burner itself and the base. Either that or just buy another burner, and try and keep it all a bit cleaner in the future :)

The Red Ace

Looking at the photo where the flame is lifting off burner there is a good possibility that the flame spreader is porous

whizbang

Is it mains or bottle gas supply..? looks like supply pressure is low if everything is clean - that includes the jet in the base of the hob, visible when you remove the 2 top bits.

In the meantime make sure your room is well ventilated while the gas is in use; its probably too much to ask you not to use it until its sorted...

Carbon monoxide alarm ?

The Continental Op

https://www.boards.ie/discussion/comment/119978315#Comment_119978315

Its burning with a blue flame that indicates full combustion rather than incomplete combustion that produces carbon monoxide. To produce a decent amount of carbon monoxide you need a yellow flame and the OP would notice that the pots get black on the bottom every time they are used.

Agree that supply pressure might be an issue. With bottled gas I've seen plenty of regulators fail so I wouldn't think twice about replacing one but OP has stated its natural gas.

There will be an adjustment which of course will lead to certain death if not adjusted by a qualified gas installer for each burner that controls the minimum setting. With the knob pulled off there will either be a small adjustment screw to the side of the knob spindle or the spindle will be hollow with a small adjustment screw at the bottom in the center.

That adjustment shouldn't affect the burner on full flame but always a possibility the someone has removed the knobs and done some over jealous cleaning and wildly changed the setting. If the burner has the correct level of flame at the low setting then its not that.

manofthefora

Apologies for delayed response to the above suggestions.

The gas supply is town gas from the mains supply.

Is there crud in the pipe feeding the spreader? I guess that's possible but I can't see any way to check other than poking my finger in a bit.

As said above, rotating the burner is not possible. There's a notch to force a single position.

No one has messed with any settings.

Spreader is porous? Is that possible? Metal just became porous?

Still not properly clean so doesn't sit snug. That's possible so I will go at it with a wire brush.

Buy a new one? It's SMEG so headed to €100 for the burner :(

Thank you to everyone for your interest.

MOTF