A thermostat works by measuring the temperature of the room it is installed in and turning the heating on or off to maintain the target temperature.
If the thermostat is installed in a hallway with no radiator, it may never reach the set temperature because the hallway is not being heated. As a result, the heating could continue running for longer than necessary, causing the heated rooms to become too warm and wasting energy.
For the most accurate temperature control, the thermostat should be installed:
In a room that has a radiator.
Away from direct sunlight, draughts, and other heat sources.
In a location that provides a good representation of the area's average temperature.
In HMOs, this is typically a communal room, such as a lounge, where the thermostat can accurately measure the temperature of the heated living space while remaining accessible to all occupants.