Following best practices is crucial for ensuring compliance with SN EN ISO 24664:2025, enabling effective pressure relief device management in refrigerating systems and heat pumps, and ensuring readiness for audits.

Best practices at a glance

This checklist outlines essential best practices that align with SN EN ISO 24664:2025 clauses, focusing on mass flow calculations, pressure drop assessments, and selection criteria for pressure relief devices. By adhering to these practices, organizations can enhance safety and operational efficiency while meeting compliance requirements.

The practices

1. Conduct comprehensive mass flow calculations.
   Proper mass flow calculations for pressure relief devices are vital to ensure they operate effectively under varying conditions. This practice minimizes the risk of device failure and potential system hazards. Refer to Clause 5 of SN EN ISO 24664:2025 for detailed guidance on mass flow assessments.

2. Evaluate discharge capacities of pressure relief valves.
   Assessing the discharge capacities of pressure relief valves is essential for maintaining system safety and compliance. Inadequate discharge capacity can lead to system overpressure and catastrophic failures. This is covered in Clause 6 of SN EN ISO 24664:2025.

3. Analyze pressure drop in inlet and outlet piping.
   Regular analysis of pressure drops in both inlet and outlet piping ensures optimal performance of pressure relief devices. High pressure drops can compromise the effectiveness of these devices, increasing the risk of system failure. Refer to Clause 7 for methodologies to evaluate pressure drops.

4. Establish selection criteria for pressure relief devices.
   Clear selection criteria for pressure relief devices should be established to ensure the right devices are used for specific applications. This reduces the risk of improper installation and enhances system reliability. See Clause 8 for criteria recommendations in SN EN ISO 24664:2025.

5. Assess the impact of internal and external heat sources.
   Understanding the influence of both internal and external heat sources is key to ensuring the safe operation of refrigerating systems. This practice helps mitigate risks associated with thermal expansion and pressure build-up, as discussed in Clause 9.

6. Account for pressure generation by compressors and heaters.
   Regular evaluations of pressure generated by compressors and heaters help maintain system integrity. This practice ensures that safety devices are correctly rated and positioned, as outlined in Clause 10.

7. Monitor thermal expansion of trapped liquids.
   Monitoring thermal expansion is crucial to prevent overpressure situations in systems containing trapped liquids. Implementing this practice protects against potential failures, as highlighted in Clause 11.

Audit preparation checklist

• Conduct comprehensive mass flow calculations.
• Evaluate discharge capacities of pressure relief valves.
• Analyze pressure drop in inlet and outlet piping.
• Establish selection criteria for pressure relief devices.
• Assess the impact of internal and external heat sources.
• Account for pressure generation by compressors and heaters.
• Monitor thermal expansion of trapped liquids.

Next steps

To deepen your understanding of ISO 24664:2024 compliance requirements, consider pursuing specialized training or acquiring an implementation guide. Accessing the standard itself will provide further insights into the nuances of compliance and best practices for refrigerating systems and heat pumps.