prEN ISO 24664 rev

Refrigerating systems and heat pumps — Pressure relief devices and their associated piping — Methods for calculation

General information

10.99   New project approved   May 27, 2026

CEN

CEN/TC 182 Refrigerating systems, safety and environmental requirements

European Norm

Scope

This document describes the calculation of:
—     mass flow for sizing pressure relief devices for parts of refrigerating systems;
—     discharge capacities for pressure relief valves and other pressure relief devices in refrigerating systems including the necessary data for sizing these when relieving to atmosphere or to part of the refrigerating system at lower pressure;
—     the pressure loss in the inlet and outlet lines of pressure relief valves and other pressure relief devices and includes the necessary data.
This document specifies the requirements for selection of pressure relief devices to prevent excessive pressure due to internal and external heat sources, the sources of increasing pressure (e.g. compressor, heaters, etc.) and thermal expansion of trapped liquid.
NOTE            The term "refrigerating system" used in this document includes heat pumps.

Related legislation

Legislation related to this standard

2014/68/EU

Directive 2014/68/EU of the European Parliament and of the Council of 15 May 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of pressure equipment

Life cycle

PREVIOUSLY

PUBLISHED
EN ISO 24664:2024

NOW

IN_DEVELOPMENT
prEN ISO 24664 rev
10.99 New project approved
May 27, 2026