Reasons for Malfunctions of Combustible Gas Detectors
Fault causes occurring during the installation and operation of combustible gas detectors are rather complicated. Main contributing factors include users' lack of understanding of instrument performance, improper model‑selection upon purchase, non‑standard installation and inadequate maintenance. Understanding these fault causes helps guide correct installation, operation and maintenance, and reduces equipment failures.
Ⅰ. Failures Caused by Improper Operation
① Prevent electromagnetic interference during operation. Anti‑interference measures shall be considered for installation position, mounting angle, protection measures and system wiring. Electromagnetic interference comes mainly from airborne electromagnetic waves, interference on power and I/O cables, and human‑body static electricity.
② Keep combustible gas detectors away from air‑conditioners and heating equipment. If cold or hot airflow blows directly onto the detector, the resistivity of the platinum wire may change and produce measurement errors. Avoid faults caused by improper location.
③ Avoid exposing the detector to high temperature, high humidity, steam and oil fume.
④ Watch out for fault‑inducing conditions such as dust, high temperature, moisture and rain exposure.
Ⅱ. Failures Caused by Non‑standard Installation
① For residential applications, install combustible gas detectors near gas pipelines and stoves in kitchens. For natural‑gas service, mount the detector within 30 cm below the ceiling. For liquefied‑petroleum‑gas service, install the detector 30‑50 cm above the floor.
② Reliable earthing is required to suppress electromagnetic interference. Poor earthing will affect voltage stability and lead to inaccurate readings. Ensure proper earthing during installation.
③ Do not place detectors and terminal blocks in locations vulnerable to mechanical impact or water ingress, which may cause open‑circuit or short‑circuit faults.
④ Non‑standard installation will trigger detection failures. For example, if the detector is not placed close to potential leak points, or is installed next to exhaust fans, leaking gas may not reach the sensor, so hazards cannot be detected in a timely manner.
Ⅲ. Required Maintenance
① Regular cleaning and maintenance can effectively prevent faults of combustible gas detectors.
② Test earthing condition periodically. Sub‑standard or missing earthing makes the detector susceptible to electromagnetic interference and results in malfunctions.
