Where should the room thermostat be located for an underfloor heating installation?

• A. Outside the room
• B. In the ceiling
• C. In the floor
• D. In the corner

Answer: (A)

The main idea is that a room thermostat should sense the temperature of the space it is meant to control. For underfloor heating, you want it to respond to the room air temperature so comfort is achieved without overshooting or undershooting. If the sensor were placed outside the room, it would mainly read outdoor conditions and weather influences, causing the heating to react to the outside environment rather than the occupants’ comfort. That leads to inefficient operation and inconsistent temperatures inside.

The best location is inside the room on an interior wall, about chest to shoulder height (roughly 1.5 meters) and away from heat sources, direct sunlight, drafts, doors, or windows. This placement gives a representative reading of the room’s actual conditions. In many underfloor heating setups, there’s also a floor sensor to limit floor temperature, while the room thermostat handles the room air temperature—so placing the thermostat in the room aligns with how the system is meant to respond to comfort needs.