The PIR Sensor works with Herschel Wifi-enabled thermostats to give you extra energy savings on your heating based on room occupancy when the heating is on. (Why have the heating on full blast in a room noone is in?).
We recommend you set up your Herschel Thermostats to run in Smart Mode as normal.
But then with the PIR sensor you can add “Scenes” to the Smartlife App (see an example Scene here) to turn the thermostat down if you are away from the room and turn it back up when you return. Say, for example, your living room is usually set for 21°C from 18:30 until 22:30, but you go out to dinner. Rather than keep heating a room you are not in, the PIR Sensor will turn your heating down while you are out.
As another example, you can also use it to keep the heating on if (for example) you are working late in a room that usually turns its heating down earlier in the evening.
The PIR Sensor is a battery operated WiFi unit. You will need one sensor for each room you want to check for occupancy. The sensor will work effectively in small to medium-size houses (e.g. 2-3 bedrooms) when paired directly to the main router. For larger buildings using network extenders, the sensors should be paired with the extenders.
The PIR sensor must be used in conjunction with a Herschel Thermostat, it will not control your heating just on its own.