Abstract: A reversible manifold collar design for use in a vertical low pressure chemical vapor deposition (LPCVD) furnace incorporates first and second notches in opposing ends thereof such that one of the notches aligns with an exhaust port in the deposition chamber of the furnace irrespective of the installed orientation of the collar. As such, blockage of the exhaust port, which might otherwise increase deposition rates and/or decrease film uniformity, may be avoided. Also, a method of retrofitting a LPCVD furnace includes removing an existing manifold collar and replacing it with a reversible manifold collar such that one of a pair of notches therein is adapted to align with an exhaust port irrespective of the orientation of the collar.