WVR SVA / SVU Dual Safety Valves with Chain Drive

Dual safety valves with two 3-way valves, one on the inlet and one on the outlet, connected by a chain drive and two safety valves dependent or independent on back pressure.

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.

Technical Features

  • available in steel or stainless steel
  • Selection of body material as per German DIN EN12284, AD2000 Series W
  • Working mediums: refrigerants as per EN 378 p. 1, e.g. NH3, R134a, R290 (propane), R507 and blends with refrigerator oil; neutral, gaseous and liquid mediums; glycol-based cold brine
  • Installation position: vertical as per AD2000-leaflet A2 and horizontal
  • Available valve seat seals (for safety valves): WVR SVAA / WVR SVUA: PTFE seal, can be used at temperatures of -60 °C to +180 °C, cannot be used for response pressures of less than 10 bar. WVR SVAB / WVR SVUB: elastomer seal, can be used at temperatures of -50 °C to +110 °C

WVR AL SVA / SVU Dual Safety Valves


steel or stainless steel

Nominal Size

DN 15-100

Nominal Pressure Level

PS 25, PS 40, PS 63

Temperature Range for Standard Valves

WVR SVAA / WVR SVUA: -60 °C to +180 °C
WVR SVAB / WVR SVUB: -50 °C to +110 °C

flanged ends as per DIN and ANSI
Additional Information
available with bursting discs, bursting disc holder and excess flow valve

Get in touch

Armaturenstr. 2
17291 Prenzlau

Phone: +49 3984 8559-0
Fax: +49 3984 8559-18