Anti-Vacuum Valve, a smart passive device designed to prevent negative pressure inside boilers

Anti-vacuum shape memory thermostatic valve

Anti-vacuum valve: functionality and characteristics

Anti-vacuum valve’s primary function is to protect thermostatic systems from collapsing because of internal vacuums and preventing negative pressure.

Infact, thermostatic anti-vacuum valves are able to restore the atmospheric pressure inside of a biphasic closed system in an extremely precise and reliable way. At the same time they also act as air vent valves during the heating phase. 


Dolphin Fluidics’ anti-vacuum valves

The key element of the Dolphin Fluidics anti-vacuum valves project is a new intelligent actuator system made of a shape memory alloy. According to the temperature it is subjected to, the system is capable of reacting to the heat without any further energy source.

Compared to the traditional systems it does not require any electrical power and can be installed in any position and orientation. The techno-polymer body, designed to withstand high temperatures, grants repeatability and reliability in a cost-effective package.

A completely new way to design and realize anti-vacuum relief valves that guarantees: no need of power supply, high accuracy and reliability and a simplified installation also for horizontal axis.


Are you interested in smart and accurate anti-vacuum valves?

Contact us to know more

Technical information

Steam/water mix. temperature - valve closed (no leakage) > 99 °C / > 210 F
Steam/water mix. temperature - valve opened (air can flow in) < 95 °C / < 203 F
Boiler pressure - valve closed (no leakage) 0.2 ± 0.1 bar / 2.9 ± 1.4 psi
Max boiler pressure 2.5 bar / 36 psi
Max temperature 140 °C / 284 F
Nominal stroke 2.2 ± 0.2 mm
Wrench size (for installation) 24 mm
Threaded inlet 1/4
Weight 12 g / 0.03 lb
Materials compliant EC 1935/2004 NSF51


For more information, please fill out the form below:

I authorize the use of my personal data in compliance with the Regulation (EU) 2016/679 (General Data Protection Regulation). Read the Privacy Policy.