Why are heat detectors generally mounted higher than smoke detectors?

Heat detectors are typically mounted higher than smoke detectors primarily because heated air rises. When there is a fire, the heat generated causes the surrounding air to become warmer and rise towards the ceiling. By positioning heat detectors higher up, they are better equipped to sense the elevated temperatures that indicate a fire has started.

Smoke detectors, on the other hand, react to the presence of smoke particles in the air, which can move and spread more evenly throughout the room. Thus, smoke detectors are often installed at or near the ceiling but can be effective at various heights to ensure they can detect smoke regardless of where it accumulates.

While avoiding false alarms, improving aesthetic appeal, and saving on installation costs are considerations in fire detection systems, the fundamental reason for the height difference between heat and smoke detectors directly relates to the physical behavior of heat in a fire scenario.