Sit 420 B3 0420003 gas valve

Gas thermostatic valve Sit 420 B3 (part number 0.420.003, analog 900.331.004) Ensure reliable and safe gas supply to your heating system with the original Sit gas valve model 420 B3 (part number 0.420.003). This automation element serves as the "heart" of the gas path, controlling fuel supply to the pilot and main burners, as well as providing protection against leaks when the flame goes out. Why choose the Sit 420 B3 valve: Reliable protection. The built-in safety mechanism is powered by a thermocouple and instantly shuts off the gas when heating stops (gas control). Stable operation. The valve is fully mains-dependent, ensuring clear opening and closing of the gas path. Versatile connection. Equipped with threaded fittings, a thermocouple ferrule, and a pilot ferrule — allows quick connection of necessary system elements. Italian quality. Manufacturer Sit (Italy) guarantees manufacturing precision and long service life. Easy integration. It is a basic gas valve without a built-in temperature regulator, compatible with a wide range of equipment. Key features: Manufacturer: Sit (Italy). Part number (SKU): 0.420.003, 900.331.004. Type: Thermostatic gas valve (series 420, modification B3). Category: Gas valves. Operating parameters: opens at current less than 200 mA, closes at current more than 40 mA. Maximum inlet gas pressure: 50 mBar. Connection: Rp ¼ (ISO 7-1:1982). Operating temperature range: 0–80 °C. Compatible models: The Sit 420 B3 valve is widely used in gas boilers and water heaters using Sit automation. Compatible with burners and boilers requiring installation of this valve series. Exact compatibility should be checked against the serial number of your equipment.