I am getting a build up in the draw of section of my syrup pan and have had to clean it off after each of the last two boils. Yesterday there was quite a bit of niter in the flu pan, but I did not notice a lot of niter on the previous boil. I usually only clean the pan once or twice at the end of the season. I am boiling on a D&G wood fired 30" x 8' evaporator. Is my syrup pan getting bad, bad depth when boiling, foaming too much, making too heavy syrup? I would like to prevent this extra work. Suggestions.