What sort of venting do I need?

A tankless must be vented to meet both Ontario and manufacturer’s specification, so we are fastidious about this particular aspect of installation. A tankless cannot be vented through a lined chimney due to safety concerns and building code regulations. To vent a tankless, a designated vent pipe is necessary, and a second pipe may also be used to bring fresh air to the tankless system, in order to completely isolated it from the home’s air. For a non-condensing tankless stainless steel vent pipe is required, as exhaust gases are very hot. A condensing tankless, which extracts some of the exhaust heat, can use 636 or another approved plastic vent piping, as the exhaust will be cooler as it exits the system.