Yes it’s true that natural and Liquid Propane gases burn much cleaner than oil, however this does not mean they are without its inherent problems. While the chief by product from an oil burner is soot, a gas appliance’s primary by product is water vapor. This may sound harmless enough, however high concentrations of water vapor in you chimney can cause major problems. Gas appliances burner much cooler than oil and require a different chimney application. While a standard oil burner may require an eight inch chimney flue, a similar gas appliance may only require five inches. An improperly sized chimney will result in poor draft and will allow the by products of combustion to sit in you chimney flue. This high concentration of moisture will be absorbed into the clay lining of the chimney and as a result of the heating/cooling process, will cause the break down of you chimney lining. Regular inspections and cleaning of you gas flue will help keep tabs on this problem, however don’t rule out installing a chimney liner to help prevent this problem altogether.

An ounce of prevention is worth a pound of cure. -Benjamin Franklin