Hello All. Some help please. Cannon Winchester Mk3 1113298 Cooker. Many years old now. All burners work fine, the oven lights to it’s low setting (‘E’), and when turned up to a cooking level (typically Regulo 6 / 400F / 200C) it should take 15 mins to reach temperature. However though the flame increases to do so, that flame level is nowhere near what it used to be, and at 15 minutes the temperature is only 250F / 125C. I have cleaned the burner, and have just changed the thermostat. It has made no dfference! Any ideas? Many Thanks.