ISO 14903:2025 pdf download,Refrigerating systems and heat pumps — Qualification of tightness of components and joints.
ISO 14903:2025 specifies the qualification procedure used to obtain type approval for the tightness (leak tightness) of hermetically sealed and closed components, joints, and parts used in refrigerating systems and heat pumps. It sets out how manufacturers should demonstrate that components and their assemblies meet the required tightness level under stresses encountered during operation, using a standardized testing/qualification approach. The standard applies to specific sizes (for example, joints up to DN 50, components with internal volume up to 5 l, and maximum weight up to 50 kg) and covers typical parts such as fittings, bursting discs, and flanged or fitted assemblies, including versions with seals. It defines qualification of tightness for the component as a whole and for the manufacturer-specified assembly, and it includes additional requirements for mechanical joints that can be recognized as hermetically sealed. It also clarifies that tightness of flexible piping made from non-metallic materials is not covered (covered elsewhere).
