My new cooker is bottled gas and did come with a pack of seperate jets so we could change as needed to get the right mix which we did as it just was not performing as it should.
You still haven't said what regulator you have. Butane runs at a lower pressure than propane so if you use a propane reg. on butane you can reduce the gas flow thus giving a bad gas/air mix.
It always amazes me the folk don't actually read the OP properly! John said " The hob we have inherited works off bottled gas." It's not new & presumably did work OK so why would it be jetted for towns gas ? Surely the problem lies elsewhere unless someone has been at 'em with a bit of wire in an attempt to clean them & enlarged the holes. It wouldn't be the first time I've seen that.
Thanks John. It's being run on Butane.
As Julie described, different jets for different gasses. sooty is probably due to the hob/cooker being shipped with town gas jets but Shirley if you have blue but unstable looking flame which it sounds as if you could still have the wrong size jets, maybe propane jets but your running butane. You don't say which you are using.
You're welcome John, here's to shiny pots !
That’s great Julie. Many thanks indeed. I will pass it onto Cara who is at home and I am sadly stuck here in the UK at the mo.
look at the little brass 'jets' on the cooker, dismantle the top parts as you would do to clean it. You will see each burner has a tiny brass jet where the gas comes out. These come in different gauges with the size engraved on them, removable with pliers and available at brico stores. Before changing them on our new cooker we had black residue and a yellow glow to the top of the flame, after changing each one we had a proper bright blue flame. You will need to persevere with each burner as each one will be a different size? it wasnt the gas I know for sure.
Thank you. I will check it out. Much appreciated.
It's poor combustion. The flames on your hob should burn a clear bright blue if they're yellowish then they are not getting enough air. Check to see if the pipes which supply the burners have not been colonised by the local spiders (seriously- you say the house has been empty for some time°
Bad combustion. It's sounds like it's burning with insufficient air. Have you the right gas/regulator combination? Propane & butane operate at different pressure & could cause this.