CSA /ANSI Z23551-4:22

CSA Preface 

This is the first edition of CSA/ANSI Z23551-4, Safety and control devices for gas burners and gas-burning appliances - Particular requirements - Part 4: Valve-proving systems for automatic shut-off valves, which is an adoption, with North American deviations, of the identically titled ISO (International Organization for Standardization) Standard 23551-4 (second edition, 2018-04). For brevity, this Standard will be referred to as "CSA/ANSI Z23551-4" throughout. This Standard is intended to be used in conjunction with CSA/ANSI Z23550, Safety and control devices for gas and/or oil burners and appliances - General requirements (adopted ISO 23550:2018, with North American deviations). This Standard supplements or modifies the corresponding clauses in CSA/ANSI Z23550 to establish the requirements for valve-proving systems (VPS). This Standard represents a modified adoption of an ISO Standard as defined by the ANSI policy on adoption of ISO Standards. This means that this Standard is modified in relation to the ISO Standard where technical deviations are permitted, provided that they are clearly identified and described. 

This Standard maintains the format and structure of the ISO Standard being adopted. Regional requirements for Canada and the USA can be found in Annex G. This Standard is considered suitable for use for conformity assessment within the stated scope of the Standard. This Standard was reviewed for North American adoption by the Z21/CSA Joint Subcommittee on Standards for Automatic Gas Controls, under the jurisdiction of the CSA Z21/83 Technical Committee on Performance and Installation of Gas-Burning Appliances and Related Accessories, the CSA Technical Committee on Gas Appliances and Related Accessories, and the CSA Strategic Steering Committee on Fuels and Appliances. It has been formally approved by the CSA Technical Committees and the Interprovincial/Territorial Gas Advisory Council. 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. This Standard has been approved by the American National Standards Institute (ANSI) as an American National Standard. 

Scope 

This document specifies safety, constructional and performance requirements of valve-proving systems (VPS), intended for use with gas burners and gas-burning appliances. It also describes the test procedures for checking compliance with these requirements and provides information necessary for the purchaser and user. This document is applicable to all types of VPS which are used for the automatic detection of leakage in a gas burner section having at least two valves designed in accordance with ISO 23551-1 and which give a signal if the leakage of one of the valves exceeds the detection limit. This document is applicable to VPS with a maximum working pressure up to and including 500 kPa for use in systems using fuel gases. This document is not applicable to VPSs for use in explosive atmospheres. 

NOTE Provisions for production control are not part of the ISO 23551 series.