I assumed that you are experienced with maintaining the burners. Just in case not, in my experience the burners have a very long life and can be rebuilt many times, provided the service parts
are available and the basic castings don't have leaks
. The key is to break them down completely and remove the carbon from the inside - particularly in the ring-shaped evaporator at the top of the burner. It takes time and patience, and a suitable solvent. I have tried both oven
cleaner and carburetor cleaner, with the help of pipe cleaners, but soak time and frequent replacing of cleaner seems to be the key.
I keep a supply of spare parts, which has been invaluable. The various seals
need regular replacement, and occasionally even the caps and spindles have to be replaced. I have been able to clean out orifices with a fine wire (they used to sell a tool with a short bit of wire attached). Probably the most replaced item is the little rack with a wire on top (pricker) - I should probably work on a way to just replace the wire in the future.
Good luck. The German burners do look nice...