Standards Development

Scope

This document specifies safety, constructional and performance requirements testing and documentation of automatic and semi-automatic shut-off valves for gas burners, gas appliances and appliances of similar use excluding use in fuel gas infrastructures (transportation and distribution systems).

This document applies to controls for use at maximum operating pressures above 500 kPa up to and including 6 300 kPa with sizes up to DN 250/10-inch for use on burners or in appliances using fuel gases, as natural gas, manufactured gas or liquefied petroleum gas (LPG).

It applies to

— commercial/industrial C/I valves;

— valves being mounted in gas installations;

— valves directly or indirectly actuated, electrically or by mechanical means;

— valves actuated by hydraulic or pneumatic means, including the pilot valves for these fluids if actuated electrically and including release valves, but not to any external electrical devices for switching the actuating energy;

— valves where the flow rate is controlled by external electrical signals, either in discrete steps or proportional to the applied signal and valves fitted with closed position indicator switches;

— this document covers the valve to be used in appliances, but not in gas transfer system outside appliances.

This document covers type testing only.

This document does not apply to valves covered under the scope of ISO 23551-1or the ISO 23555 series.

Purpose

The market for gas-fired appliances includes indoor/outdoor cooking appliances and small decorative and non-decorative space heaters, to whole house heating furnaces and boilers as well as light commercial/industrial applications. This market is vast and well established. Gas burner ignition system components are a common and essential part of many of these appliance operational systems. The proposed revision of ISO 23551-11 is intended to add optional construction, performance and testing requirements for gas burner ignition system components.

Original equipment manufacturer (OEM) customers of these devices prefer to purchase components that have been evaluated to some criteria that provides a minimum level of assurance that these components will perform and function as specified throughout the life of the product. In addition, end users of the heating appliance benefit greatly by expecting fewer failures of these components in the application, resulting in fewer service calls and replacement costs.

As a result, there is an identified need by component manufacturers (i.e., suppliers) to include in this International Standard, optional requirements for the evaluation of these devices. This amendment will allow manufacturers to evaluate their components that serve their customer’s needs.

In North America and perhaps other parts of the world, minimum standards exist for the evaluation of burner ignition system components identified under the scope of this proposed Revision. The proposal is based in large part on existing requirements in the US/Canadian safety standard, ANSI Z21.

20CAN/CSA-C22.2 No. 60730-2-5UL 60730-2-5, Automatic electrical controls for household and similar use – Part 2-5: Particular requirements for automatic electrical burner control systems. Just as important to the justification of this new work item is the scope of the relevant Technical Committee, ISO/TC 161, Controls and protective devices for gas and/or oil burners and appliances. The components of such controls are well defined as being under the scope of this TC. Although the proposed amendment primarily addresses durability and performance of these devices, the safety of the control systems and components in the end application is vitally important. In addition, the scope of TC 161, or the Strategic Business Plan, does not limit itself to only safety, and therefore performance related requirements such as these are indeed justified.