Zone valve

In the interest of improving efficiency and occupant comfort, such systems are commonly divided up into multiple zones.

A simpler variant of the motorized design omits the switch that detects the valve position.

In an alternative design, the motor continues to turn, while a slip clutch allows the valve to be pushed against a mechanical stop.

This style of zone valve operates with a perfectly ordinary SPST thermostat.

Highly sophisticated systems may use some form of building automation such as BACnet or LonWorks to control the zone valves.