Motorised valves are used to control water flow from the boiler to heating and hot water circuits, and is operated electrically.
Types of motorised valves:
A motorised valve can be a 2 port valve or a 3 port valve.
2-port - The valve has 2 pipe connections (ports) and permits or blocks flow between the ports depending on whether it is actuated or not. Flow is permitted when the valve is actuated and blocked in its resting state.
3-port - The valve has 3 pipe connections, in a T formation. The centre leg of the T is the inlet and the two short arms are the outlets, usually referred to as ports A and B. Actuation controls whether the flow from the inlet passes to the A or B port. In the resting state flow is to the B port (usually the hot water circuit).
Actuated valves are the mechanism for opening and closing the valve, an actuator requires a control signal and a source of energy. Actuators may be only to open and close the valve, or may allow intermediate positioning; some valve actuators include switches or other ways to remotely indicate the position of the valve.
Valves and Actuators are two completely separate components; however, they do work together to accomplish a common task.