Vacuum relief valveworking principle

The shortest, lightest, and only backflow preventer with a stainless steel body—Ames Deringer™ is the perfect fit for tight mechanical rooms and lean installation teams. With patented Dual-action™ check technology built into every Deringer, you get maximum pressure downstream of the backflow preventer. Deringer backflow assemblies are the lightest on the market, making them easier to ship and install and friendlier on your budget and timeline. When the job calls for the perfect fit on a tight timeline, the job calls for Deringer.

These vacuum safety release valves are not factory pre-set, so they can be adjusted in the field. They are a "proportional" relief valve and not "pop" type safety valve. They have a brass body with stainless steel springs & poppet. Max temperature +120°C (250°F).

Vacuum Relief valvewater heater