Fusible plugs are safety devices that contain a material that melts at a specific temperature, venting the pressure. Castel has decided to classify these devices, according to Directive 2014/68 EU, as safety devices on specific pressure equipment belonging to Risk Category I. Therefore they cannot be installed, as
the sole safety devices, on pressure equipment in Risk Categories greater than I.
Fusible plugs are basically used to protect the components in a refrigerating system or heat pump against possible overpressure, with regard to the operating conditions for which they have been designed, caused by an external heat source with excessive heat, such as fire.