ISO 5149-2:2014

Overview

ISO 5149-2:2014 - Refrigerating systems and heat pumps - Safety and environmental requirements - Part 2: Design, construction, testing, marking and documentation sets technical requirements for the construction, testing and documentation of refrigerating systems and heat pumps. It applies to piping, components, materials and ancillary equipment not covered in other parts of ISO 5149, and covers new systems, extensions/modifications and relocated/used systems. The standard excludes motor‑vehicle air conditioners and-except for associated safety devices-secondary heat‑transfer circuits. ISO 5149‑2 is intended to ensure safe, environmentally responsible design and installation practices for stationary and mobile refrigerating systems, including heat pumps.

Key topics and technical requirements

• Scope and applicability - Applies to refrigerating systems of all sizes, secondary cooling/heating systems, location considerations, and conversions to alternative refrigerants.
• Components and piping - Requirements for piping joints, isolating valves, receivers, dryers, filters, safety devices and flexible elements.
• Materials - Guidance on suitable materials (cast iron, steel, stainless steel, copper, aluminium, alloys) and compatibility with refrigerants (including special notes for ammonia and halogenated refrigerants).
• Testing and commissioning - Requirements for component and assembly testing, leak tightness, pressure relief arrangements and intrinsic safety testing (see Annex D).
• Safety devices - Requirements for safety valves, bursting discs and pressure‑limiting devices, plus examples of relief device arrangements (Annex E) and allowable discharge piping lengths (Annex F).
• Marking and documentation - Obligations for marking components and providing documentation for installation, operation, testing and maintenance.
• Special provisions - Additional normative requirements for ammonia systems (Annex B) and guidance on stress corrosion cracking (Annex G).
• Normative references - Integrates related standards such as ISO 817 (refrigerant designations), ISO 4126 (safety devices) and relevant IEC product standards.

Practical applications and who uses it

ISO 5149-2:2014 is used by:

• Refrigeration and HVAC design engineers and system integrators for safe system design and material selection.
• OEMs and component manufacturers to ensure components meet safety and marking requirements.
• Installers, commissioning engineers and maintenance teams for testing, commissioning and documentation practices.
• Safety managers, inspectors and regulators to evaluate compliance with recognized safety and environmental requirements.
• Facilities that convert systems to new refrigerants or relocate equipment.

Benefits include improved operational safety, reduced environmental risk from refrigerant leakage, and clearer documentation for lifecycle management.

Related standards

• ISO 5149-1, ISO 5149-3, ISO 5149-4 (other parts of the series)
• ISO 817 (refrigerant designation)
• ISO 4126-1 / -2 (safety valves, bursting discs)
• IEC 60335 series and IEC 60204-1 (electrical safety for appliances and machinery)

Keywords: ISO 5149-2:2014, refrigerating systems, heat pumps, design, construction, testing, marking, documentation, safety and environmental requirements, refrigerants, ammonia, piping, components.