SENTINEL™ Degassing Valves

Automatically Vent Gasses and Vapors in
Pumping Systems.

Certain chemicals commonly used in metering and dosing applications are prone to outgassing. Other chemicals produce hazardous vapors that can escape the system at pump startup. A metering pump that has been off for a period of time can lose its prime and won’t pump fluid due to gas in the pump and discharge line. In all of these situations, gasses and vapors in a pumping system must be properly vented.

degassing valve
degassing valve degassing valve

Gasses and Vapors
Must Be Properly Vented.

Unvented gasses can accumulate and alter the pump flowrate or cause the pump to vapor lock.

Hazardous vapors can escape the system at pump startup, endangering personnel and damaging equipment.

Flow and metering instrumentation can give inaccurate readings due to gas or vapors in the system.

Pump priming can be difficult when there is unvented gas in the pump and discharge line.

How it Works.

Degassing valves are typically installed on a T-connection at the highest point in the piping system with the discharge port piped back to the supply tank or other safe location. In applications using chemicals that typically outgas, degassing valves can be installed on both the inlet and discharge side of the pump for maximum venting.

When the system is operational, process fluid fills the valve chamber which raises an internal float to seal the discharge port (closed valve). As the fluid outgasses and excess gas accumulates in the chamber, the float drops to open the valve. Fluid pressure then pushes the gas out through the open discharge port and back to the supply tank. Once accumulated gas is vented, the float rises again to close the valve. This process repeats automatically to safely and efficiently vent excess gas or vapor from the system.


All components used, including the internal float, are constructed of a single material for maximum chemical and thermal compatibility.

PVC, CPVC and PVDF models with 1/2” NPT, BSP, socket weld, and union connection options.

Unique internal mesh secures the float in place and filters out larger particles.

Maximum 150 psi (10.3 bar) pressure rating.

Valve Dimensions


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