When mounting heat detectors on the ceiling, they must be located no less than how many inches from the sidewall?

The correct distance for mounting heat detectors from the sidewall is a minimum of 4 inches. This guideline is important for ensuring the proper operation of the heat detector. If a heat detector is too close to a wall, it may not function optimally due to the potential for airflow disruptions caused by the wall, which could prevent the detector from effectively sensing temperature changes in the environment.

Additionally, the placement of heat detectors is designed to allow for an adequate convection current, which helps the detector quickly respond to rising temperatures. By adhering to the 4-inch minimum distance from the wall, the risk of obstructions that might affect the detector's performance is minimized, ensuring a higher likelihood of accurate readings and timely activation in case of a fire. Proper installation based on these specifications plays a crucial role in the overall effectiveness of fire alarm systems.