Sorry if this question has been answered previously. I did the search and didn't find it. I have a brinkman bullet smoker that uses wood chunks and charcoal. Those wood chunks burn down to ash. So I bought and used a Palm Springs vertical gas smoker this weekend. Chips were recommended in the manual. They smoked for about 30 minutes and stopped. When I checked the chip tray the chips were black. I replaced them and 30 minutes later the same thing happened. Should the turn to ash?