Nuclear power station, Sizewell B, relies on Parasense refrigerant monitors to protect chiller equipment.

Nuclear Power Station Selects Parasense for Continuous Monitoring of Chillers

In Case Studies, Parasense by Bacharach

Sizewell B is a nuclear power station on the Suffolk coast. It has been generating electricity for the grid since 1995. Like most IT equipment, their control systems require cooling; as part of a sophisticated safety system, Parasense monitors the chillers for refrigerant leaks.

Refrigeration at Sizewell B

The control systems at Sizewell B are cooled by 14 safety-compliant chiller systems, over four separation groups. Between them, they provide a high degree of resilience and redundancy.

Since the power station first went into operation, the original chillers have been modified during routine maintenance to comply with updated F-Gas regulations.

Refrigerant Leak Detection

As part of the project, refrigerant leak detection was specified. They regonized that the reliability of this equipment was key, and engineers at Sizewell B made the safety case for Parasense equipment to monitor the chillers and surrounding areas, 24/7.

Parasense supplied nine 16-channel GRM2 infrared refrigerant leak detection systems. Each operates independently, monitoring a chiller system, including the valves and air handling units.

Each Parasense unit has its own control panel with warning beacons fitted in the plant room.

Delivering the Project

The Parasense equipment was installed during a routine maintenance shutdown by a team from Parasense and Sizewell B. To ensure compliance with the stringent safety procedures, a joint team of engineers from Sizewell B and Parasense carried out most aspects of the installation.

The final calibration and commissioning were completed by Parasense staff. All of the necessary documentation was created by the joint Parasense and Sizewell B team.


The Parasense refrigerant leak detectors form an integral part of documented refrigeration maintenance procedures, although they have as yet only detected small refrigerant losses, during planned engineering works.

Since they were commissioned, the Parasense systems have operated continuously, requiring only routine maintenance and calibration.