Hi, I have a gas cooker-oven with 4 gas hobs and over the course of the last two years two hobs stopped producing good volume of flame so I stopped using those hobs ages ago and I have veen managing with the other two. Now the other two also started producing very weak flames just like the previous two hobs. The flames are so low that the cooker is not usable as its current state unless I cook a very simple thing like omelette.
I have tried cleaning the hob heads (not sure of the exact name) for gunk, also cleaned the igniter bit, with a needle. Not sure if did a good job or not, but tried. Despite that, not much change in the volume of the flames.
To me it means either i couldn't clean the gunk properly or perhaps the problem is elsewhere.
I know I should get it looked into. Would it be a registered gas engineer? Or oven specialist? Or just replace the old thing as it is approx 18 years old and admittedly i havent cleaned it much over the years 
so it looks even older.
A quick google search tells me the cost of repair of a gas hob cooker/oven like mine could be around 130 pounds by Curry's repair service but I could buy a new cooker oven, one with an additional 100 - 150 pounds which hopefully lasts another 18 years. So it might be worth getting a new one rather than spending money on the old one looked at.
Does anyone have any experience of rescuing a gas oven cooker in this state?
How long a standard life expectancy of a gas cooker/oven?
By the way, the oven bit (as opposed to the top of the cooker hobs) seems to be working okay at the moment so half of the appliance is still usable.
Thanks in advance.