Lennox EL296UHV Installation Instructions Manual page 66

FOR THE PROVINCE OF ONTARIO, HORIZONTAL SIDEWALL VENT APPLICATIONS ONLY
For exterior horizontal venting applications, the 2" X 1.5"
reducer for 2" venting at the point where the exhaust pipe
exits the structure is not required in direct or non­direct vent
applications in the Province of Ontario. In these applica­
tions, the vent should be oriented such that the exhaust
plume is unobjectionable. If the installation requires more
separation between the flue gases and the building struc­
ture, a reducer may be installed on the exhaust pipe to in­
crease the flue gas velocity.
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