How can a light fire?

You could try first taking apart as much as you are comfortable with and giving the thing a good hoovering/brushing out first,I had a gas fitter out and he was embarrased taking my money (still did :) when it just needed cleaned.The fire draws air in all the time to burn the flame in doing so it draws dust/pet hairs/human hair and all sorts of rubbish in nomatter how good your cleaning is,all thes muck blocks the airways for the pilot jet that is sucking the air in,get the hoover nozzle and a small brush in and give it a thorough clean,it wont cost you anything but 5 mins work and might fix it,after that look to the thermocouple.

a
February 2017

Possibly the pilot is poorly adjusted, sooted up, dirty or a combination of the foregoing and isnt playing properly on the flame failure thermocouple. Possibly the thermocouple connection is poor or possibly the thermocouple has failed.

The manual should show you what to look for in the pilot flame. If you dont have a manual you may be able to find one at the Cannon website.

xxx
February 2017