A solenoid valve is an electromechanical valve for use with liquid or gas controlled by running or stopping an electrical current through a solenoid, which is a coil of wire, thus changing the state of the valve. The operation of a solenoid valve is similar to that of a light switch, but typically controls the flow of air or water, whereas a light switch typically controls the flow of electricity. Solenoid valves may have two or more ports: in the case of a two-port valve the flow is switched on or off; in the case of a three-port valve, the outflow is switched between the two outlet ports.

Solenoid valves may use metal seals or rubber seals, and may also have electrical interfaces to allow for easy control. Multiple solenoid valves can be placed together on a manifold

A spring may be used to hold the valve opened or closed while the valve is not activated.

A common use for 2 way solenoid valves is in Central Heating. The solenoid valves are controlled by an electrical signal from the thermostat to regulate the flow of heated water from a heat pump to the in room radiators. Such valves are particularly useful when multiple heating zones are driven by a single heat pump. Commercially available solenoid valves for this purpose are often referred to as Zone valves. a common use for 3 way solenoid valves are as pilot valves for other valve types, such as air operated angle seat valves/globe valves

There are a number of different manufacturers of solenoid valves. Some examples are:

• FESTO ^*
• Danfoss ^*
• SMC Corporation of America ^*
• PHD, Inc. ^*
• Norgren Pneumatics ^*
• Bimba Manufacturing Company ^*

Technical information on the function and application of Solenoid Valves

valves