When converting a furnace, how far above the burner must the flue collar be?

In the context of furnace conversions, the requirement for the flue collar height above the burner is crucial for proper venting and operation of the furnace. A height of 12 inches above the burner is specified to ensure that there is adequate clearance for combustion gases to rise and exit efficiently through the flue, preventing potential backdrafts and ensuring that the furnace operates within safety standards.

This distance helps maintain an appropriate draft and minimizes the risk of the flue gases making contact with combustibles, which is vital for safety. Following this standard height of 12 inches allows for the optimal functioning of the furnace while adhering to safety regulations set forth by technical standards authorities. It is essential for avoiding issues related to improper venting that could lead to carbon monoxide buildup or decreased furnace efficiency.