We had a new gas cooker installed by a Corgi/Gas Safe installer recently, but I've just noticed that all of the flames change over a very small area of the knob. In other words, the knobs rotate 90degs from max to min, but all the flame variation happens over just a few degrees, which doesn't tally with the markings on the knobs. Does anyone know whether the cooker hasn't been installed correctly, or is it a problem with the actual cooker? It's an Indesit K6G210WG.

Trev, April 2009