Can someone give me the chemical make up, or any information, of the white chalky ash that is sometimes produced when carbon monxide is created. I have found it many times when doing a carbon monoxide test on heating systems and carbon monxide was found. I have not found, it that I remember, if carbon monoxide was not found.

Hard to say. Natural gas forms no ash, and oil, very little. Could it be zinc oxide from acids in the combustion fumes attacking the galvanized ducts? If you know much about HVAC, stick around. Bunch of questions here not getting that good of answers.