The Ontario Building Code | Design and Installation Requirements
9.33.1.1. design and installation Requirements
(1) The design and installation of central heating systems, including requirements for combustion air, shall conform to Part 6 and this Section.
(2) The design and installation of air-conditioning systems shall conform to Part 6.
(3) Repairs or component replacements that change the capacity or extent of safety of an existing heating, ventilating or air-conditioning system and that alter the method of operation shall conform to this Code.