(Some core definitions are replicated here.)
electronic TRV (eTRV)
- TRV where the integral thermostatic valve controller is electronic and programmable. Uses an electronic temperature sensor and microcontroller. May be programmable by means of a USB port or wirelessly; may have an LCD interface and buttons. "Integral" here means that the electronic valve controller is built into the valve head or connected to it by a cable or by a one-to-one wireless connection with a wall-mounted unit.
intelligent TRV (iTRV)
- Electronic TRV where the integral thermostatic valve controller bases the target temperature on additional information such as room occupancy. It is capable of being influenced by other heating system components and is capable of transmitting information to other heating system components such as a boiler controller.