CSA P.3:15 (R2025)

Description

Preface This is the third edition of CSA P.3, Testing method for measuring energy consumption and determining efficiencies of gas-fired and fuel oil-fired water heaters . It replaces the previous editions, published in 2004 and 1998 under the title Testing Method for Measuring Energy Consumption and Determining Efficiencies of Gas-Fired Storage Water Heaters. The test method in this edition is harmonized with the test procedures for residential and commercial water heaters in the US Department of Energy (DOE) Code of Federal Regulations, published on July 11, 2014. The scope of this Standard has been expanded to include certain residential water heaters and certain commercial water heaters that were not covered in the previous edition of the Standard. The revised test method is considered to be more representative of conditions encountered in field operation and provides greater accuracy and repeatability of the test results. The test method applies the same energy efficiency descriptor (Uniform Energy Factor (UEF)) to all residential and certain commercial water heaters that are utilized in residential applications. Additional revisions to the test procedures include: a) an update of the simulated-use-test water draw pattern where multiple draw patterns are used for testing water heaters as a function of appliance capacity to be more reflective of actual field usage, based on recent field test data; and b) an update of the outlet water temperature requirement to better reflect conditions encountered in typical field installations. This Standard is considered suitable for use for conformity assessment within the stated scope of the Standard. CSA Group acknowledges that the development of this Standard was made possible, in part, by the financial support of Natural Resources Canada (NRCan), the Ontario Ministry of Energy (OME), and Efficiency Nova Scotia (ENS). This Standard was prepared by the Subcommittee on Gas-Fired Storage Water Heaters Efficiency, under the jurisdiction of the Technical Committee on Energy Efficiency and Related Performance of Fuel- Burning Appliances and Equipment and the Strategic Steering Committee on Fuel Burning Equipment, and has been formally approved by the Technical Committee. 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 describes the test procedures required to perform a 24 h simulated-use test. This Standard also provides the calculations required to determine the first-hour rating, maximum flow rate, recovery efficiency, standby loss, daily water heating energy consumption, uniform energy factor, and annual energy consumption for gas-fired and fuel oil-fired water heaters. 1.2 This Standard applies to: a) Gas-fired storage water heaters i) with rated storage capacity up to and including 454 L (120 US gal); ii) having rated inputs up to and including 30.77 kW (105 000 Btu/h); and iii) designed to provide outlet hot water at a controlled temperature up to and including 82 °C (180°F); b) Fuel oil-fired storage water heaters i) with rated storage capacity up to and including 454 L (120 US gal); ii) having rated inputs up to and including 41.03 kW (140,000 Btu/h); and iii) designed to provide outlet hot water at a controlled temperature up to and including 82 °C (180°F); c) Gas-fired instantaneous water heaters i) with rated storage capacity up to and including 7.6 L (2 US gal); ii) having rated inputs up to and including 73.25 kW (250 000 Btu/h); and iii) designed to provide outlet hot water at a controlled temperature up to and including 82 °C (180°F); and d) Oil-fired instantaneous water heaters i) with rated storage capacity up to and including 7.6 L (2 US gal); ii) having rated inputs up to and including 61.53 kW (210 000 Btu/h); and iii) designed to provide outlet hot water at a controlled temperature up to and including 82 °C (180 °F). 1.3 The tests contained in this Standard provide a standardized method of comparing performance and efficiency. 1.4 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. 1.5 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.