Question

Hi Tom, my Dometic fridge gas viewer window in fridge shows a red sooty type flame, I have cleaned the jet many times after which it shows the correct blue coloured flame. Do you think a blast of compressed air is the only answer!

Answer

This would be the first thing I would do. Compressed air tends to dislodge anything living in your gas burner. If you have cleaned the complete burner and flue tube every time you clean the jet, then this could possibly indicate a problem with the gas valve supplying an inadequate gas supply to the burner thus over aerating the flame causing an orange flame.