AWP dual safety valves are designed to be used as relief or overflow valves in the refrigerant cycles of industrial refrigeration systems. They are available with safety valves either back pressure dependent or independent to protect the refrigeration systems and their components from excess pressure (see also EN 378 part 2). They comply with AD2000 regulations. After their initial response AWP safety valves open within 10 % of pressure increase up to the designed limitation. They close within a pressure drop of 10 % below the response pressure. The 3-way valves enable easy checks and maintenances of the safety valves without the system’s operation to be interrupted. One of the 3-way valves’ two outlet nozzles is always open whereas the other one is closed. The chain drive between the two 3-way valves ensures that both 3-way valves open to the same safety valve. So one safety valve can be checked or removed while the other one remains in service to protect the system.