User Guide
1
A solenoid is a simple form of an electromagnet consisting of a coil of
insulated copper wire.
A solenoid valve is an electromechanical valve frequently used to control
the flow of liquid or gas.
Definitions
Solenoid valves are found in many applications and are commonly used in
refrigeration and air conditioning systems. Their function is simply to turn
refrigerant flow on and off.
Function
Solenoid valves offer fast and safe switching, reliability, long life and compact design.
Benefits
A solenoid valve operates in the following way:
Stage Description
1 When the solenoid coil is electrically energized, it produces a
magnetic field that attracts iron and many of its alloys.
2 An iron armature or plunger (shown in Figure 1) is drawn up
into the core of the solenoid.
3 A stem and pin or poppet attached to this plunger opens the
valve port.
4 When the solenoid valve is de-energized, the plunger falls, and
the poppet closes the valve port.
Note: This magnetic principle constitutes the basis of design for all solenoid valves.
Operation
Figure 1 shows the parts of a solenoid valve.
Diagram of solenoid valve
Because solenoid valves are electrically operated, their on-off function can
be controlled automatically by suitable control systems. This function is
extremely important, in terms of system performance.
Role in system
performance
Basic operation of solenoid valves
Figure 1