EN ISO 14903:2025

Overview

EN ISO 14903:2025 - "Refrigerating systems and heat pumps - Qualification of tightness of components and joints" is a CEN-endorsed adoption of ISO 14903:2025. It defines a type‑approval qualification procedure to verify the tightness (leak integrity) of hermetically sealed and closed components, joints and parts used in refrigerating systems and heat pumps. The standard applies to joints up to DN 50 and components with internal volume ≤ 5 L and weight ≤ 50 kg, and covers metal flexible piping and assemblies with various seal materials and designs. It supersedes ISO 14903:2017.

Key topics and requirements

• Scope and applicability: qualification of hermetically sealed and closed components, mechanical joints eligible as hermetic, and assemblies used in refrigeration and heat pump installations; excludes non‑metallic flexible piping (covered in ISO 13971).
• Test requirements: definition of tightness levels and acceptance criteria for components and assembled parts as supplied by the manufacturer.
• Sealed system provisions: requirements specific to sealed assemblies and manufacturer-specified assembly procedures.
• Test procedures: sampling, test temperature, tightness test methodology and tightness‑level control.
• PTV (pressure‑temperature‑vibration) testing: updated methodology - removal of the integrated vibration method and retention/clarification of the combined pressure‑temperature cycle with a separate vibration test.
• Additional tests: operation simulation, freezing tests, vacuum tests, compatibility screening with test fluids, and fatigue testing for hermetically sealed joints.
• Joint requirements: torque control for reusable joints, additional pressure tests for hermetic joints and pass/fail criteria for sealing elements.
• Documentation: required test report content and the minimum information suppliers must provide to testing bodies.

Applications and practical value

• Ensures reliable refrigerant containment, improving safety and environmental compliance (lower fugitive emissions).
• Supports type approval and product certification for valves, fittings, bursting discs, flanged assemblies, metal flexible hoses and other refrigerant-containing components.
• Used for design validation, quality control, supplier qualification, and regulatory compliance checks.
• Helps manufacturers demonstrate conformity with industry best practice and with requirements referenced in the ISO 5149 series for refrigerating systems and heat pumps.

Who should use this standard

• Component manufacturers and suppliers in HVAC‑R
• Test laboratories and certification bodies performing tightness/type approval tests
• System designers, installers and maintenance organizations seeking validated components
• Authorities and compliance assessors enforcing refrigerant safety and environmental rules

Related standards

• ISO 5149 (refrigerating systems and heat pumps - safety and environmental requirements)
• ISO 13971 (tightness testing for flexible piping made from non‑metallic materials)
• EN ISO 14903:2017 (previous edition - superseded)

This standard is essential for professionals focused on leak testing, component qualification and regulatory compliance in refrigerating systems and heat pump applications.