ASERCOM has published the fourth revision of its “Components for Systems Using Flammable Refrigerants” guideline, providing guidance on component requirements and applications in vapour compression systems using flammable refrigerants within the framework of European RACHP standards. The latest revision is dated October 2026.
The guideline covers valves, heat exchangers, compressors and other mechanical, electronic and electro-mechanical controls for systems operating in non-hazardous, or non-ATEX, areas. It addresses EN safety standards, risk assessment, component requirements, ATEX and the Pressure Equipment Directive (PED), as well as components used as mitigation measures.
According to ASERCOM, systems using flammable refrigerants can use components qualified for the specific refrigerant, while component manufacturers must specify application ranges and approvals such as ATEX where applicable. The system manufacturer remains responsible for designing a safe system and ensuring that it is designed, installed and serviced according to applicable safety standards and local regulations.
The guideline also addresses mitigation components intended to detect and mitigate flammable atmospheres before they reach the lower flammability limit (LFL) in occupied spaces or machinery rooms. Examples include shut-off valves, gas detectors, ventilation fans and circulation airflow fans.
Eight annexes provide further guidance, including application examples for an R290 chiller, split and multi-split air-conditioning systems, a self-contained commercial refrigeration appliance, a remote condensing unit, rooftop ducted equipment and a ventilated enclosure. Additional annexes clarify the ATEX directives and PED requirements.
