Pertains to the following electrically driven, mechanical, vapour-compression-type systems: a) large air conditioners and heat pumps rated above 19 kW (65000 Btu/h) cooling or heating capacity at standard rating conditions for both single- and three-phase electrical power supplies; and b) all sizes of single packaged vertical air conditioners and heat pumps and air-conditioning condensing units.

Preface This is the fourth edition of CSA C746, Energy performance rating for large and single packaged vertical air conditioners and heat pumps. It supersedes the previous editions published in 2006, 1998, and 1993 under the title Performance Standard for Rating Large Air Conditioners and Heat Pumps. This Standard provides methods for rating factory-designed and prefabricated air-conditioning or heat pump equipment above 19 kW (65 000 Btu/h). Requirements for all sizes of single packaged vertical units are provided. It also specifies minimum energy efficiency levels. The changes in this edition are as follows: updated test procedures and requirements for large air-conditioners and heat pumps and single packaged vertical units to align with the U.S. Department of Energy (DOE). minimum energy efficiency levels have been updated to be consistent with the levels in ASHRAE 90.1-2016, Energy Standard for Buildings Except Low-Rise Residential Buildings This Standard is compatible with the following Air-Conditioning, Heating and Refrigeration Institute (AHRI) Standards: 340/360-2007, Commercial and Industrial Unitary Air-Conditioning and Heat Pump Equipment 365-2002, Commercial and Industrial Unitary Air-Conditioning Condensing Units 390-2003, Performance Rating of Single Package Vertical Air-Conditioners and Heat Pumps CSA acknowledges that the development of this Standard was made possible, in part, by the financial support of Natural Resources Canada (NRCan) and Independent Electricity System Operator (IESO). Scope 1.1 This Standard applies only to the following electrically driven, mechanical, vapour-compression-type systems: a) large air conditioners and heat pumps rated above 19 kW (65 000 Btu/h) cooling or heating capacity at standard rating conditions for both single- and three-phase electrical power supplies; and b) all sizes of single packaged vertical air conditioners and heat pumps and air-conditioning condensing units. Note: See Tables 1 to 3 for classifications of air conditioners, heat pumps, and air-conditioning condensing units. 1.2 In this Standard, \"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 (non-mandatory) to define their application. 1.3 The values given in SI units are the units of record for the purposes of this Standard. The values given in parentheses are for information and comparison only.