CSA C273.5:11 (R2020)

Preface This is the second edition of CSA C273.5, Installation of air source heat pumps and air conditioners . It supersedes the previous edition published in 1980. It covers installation of unitary, factory-assembled air conditioners and heat pumps (air sink and air source) up to 19 kW (65,000 Btu/h). It should be noted that this edition now includes requirements for air conditioners as well. This Standard has been developed in compliance with Standards Council of Canada requirements for National Standards of Canada. It has been published as a National Standard of Canada by CSA Group. Scope 1.1 This Standard covers the installation requirements for unitary air conditioners and air source heat pumps for residential applications with cooling ratings up to 19 kW (65 000 Btu/h). 1.2 This Standard covers installations in new construction and, where applicable, in installations that are part of an existing system. 1.3 This Standard covers equipment requirements, system design, equipment selection, minimum installation requirements, and information to be provided to the owner. 1.4 In CSA standards, "shall" is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; "should" is used to express a recommendation or that which is advised but not required; and "may" is used to express an option or that which is permissible within the limits of the standard. Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material. Notes to tables and figures are considered part of the table or figure and may be written as requirements. Annexes are designated normative (mandatory) or informative (nonmandatory) to define their application. 1.5 The values given in SI (metric) units are the standard. The values given in parentheses are for information only.