How does a heat detector primarily detect smoke?

A heat detector primarily detects smoke by sensing a change in temperature. This type of device is designed to activate when it detects an increase in temperature that occurs due to a fire. When a fire generates heat, the surrounding temperature rises, which the heat detector senses, triggering an alarm.

While many smoke detectors do identify smoke particles, this is not the mechanism of action for heat detectors. Heat detectors are specifically engineered to respond to thermal changes rather than the presence of smoke itself. They also do not rely on sound levels or optical sensors, which are typically features of other types of detection methods, such as sound alarms or photoelectric smoke detectors. Thus, the focus on temperature change is what distinguishes this type of detector and makes it effective in fire situations where smoke is not yet present or visible.