This indicator warns that the gas sensor is not working properly. Contact a Homplex representative to identify the cause and/or replace the methane gas detector. As long as the yellow LED is lit, the detector does not measure and does not respond if the dangerous level of methane gas in the room is exceeded!

After powering up, wait 15 seconds for the self-test process to complete. When this process is complete the red and orange LEDs will go out and the green LED will light solid. Press the Test button for 5 seconds to verify. The detector will acoustically and visually signal a possible danger and send a signal to close the solenoid valve.

The unpleasant and easily recognisable smell (an unpleasant sulphurous odour) of natural gas used in homes is due to odorant additives, such as tert-butylthiol, which are used for safety. Most people can detect this smell at fairly low levels of gas concentration (2% L.I.E. or less), but certain disabilities or advancing age can lead to a reduction in this smell sensitivity. The L.I.E. (Lower Explosive Limit) of the gas defines the minimum volume ratio of combustible gas or vapour in the air in which an explosive atmosphere will form. The detector is calibrated to trigger the alarm at the threshold of 10% of the L.I.E. of the detected gas. Thus, it is possible for a person to smell gas before the alarm is activated. This does not necessarily indicate a fault in the device. For humans, a gradual increase in gas concentration may also go unnoticed due to olfactory fatigue.