I have a 10 year old Ducane 1504 which I love. When I turned it on the right side had orange flames come out from the knob so I turned it off. I removed the tube tried to clean it by tapping it and using a wire brush. after repositioning it the flames through the knob are gone. however, the flame is high and orange. The left side has a low blue flame - the way I think its supposed to work. Does anyone know what the problem is and how I can fix it? Is the grill safe to use?

Grilling - Ducane - Standard 1504 (LP) Grill