Line-type heat detectors should be located at what maximum distance from the ceiling?

Line-type heat detectors are designed to monitor temperature changes along a length of cable or wire. Proper installation is crucial to ensure their effectiveness in detecting potential fires.

The maximum distance from the ceiling for these detectors is typically specified to optimize their sensitivity to significant heat changes in the environment. This distance is determined based on the expected airflow and temperature stratification in the space where the detector is installed. The correct maximum distance of 20 inches allows the line-type heat detectors to be close enough to the ceiling to accurately detect heat generated by a fire while considering the delay that could occur due to thermal layering in the upper areas of a room.

In situations where the maximum distance exceeds 20 inches, there is a risk that the detector may not respond promptly enough to an increase in temperature, potentially compromising the fire alarm system's effectiveness. This critical installation parameter helps to ensure the system operates reliably and meets safety codes and standards.