Altecnic 311 Series safety relief valves are used in heating systems to safeguard the boiler and other components, as well as in household hot water systems to protect the hot water cylinder. The valve is chosen based on the preset pressure that is needed. When the discharge pressure is achieved, the valve opens and releases the pressure to the atmosphere, keeping the system's pressure from rising to levels that would be dangerous for the boiler, hot water storage cylinder and any nearby employees.