Code Library › Volume 1 › Section 9.33 — Heating and Air-Conditioning
PART 9 — HOUSING AND SMALL BUILDINGSUpdated for the 2024 Ontario Building Code

9.33.5.1.Capacity of Heating Appliances

(1) The heating system capacity shall be based on the heating load calculated in accordance with Sentence 9.33.4.1.(1). (2) Where a cooling system is installed, the cooling system capacity shall be based on the cooling load calculated in accordance with Sentence 9.33.4.1.(1). (3) The oversizing and undersizing of heating and cooling equipment capacities shall be determined in accordance with the requirements of CSA F280, “Determining the required capacity of residential space heating and cooling appliances.”
← Previous9.33.4.9. Contaminant TransferNext →9.33.5.2. Installation Standards (See also Article 9.33.5.

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Code text is reproduced for reference from the Ontario Building Code (O. Reg. 163/24, 2024 Building Code Compendium). This page is provided for general information and is not an official copy. Always verify requirements against the official Ontario Building Code and confirm with your local building department.