The alarm sound pattern is four short alarm beeps. The red LED will flash while in alarm mode.
One 'chirp' every 30 seconds is an indication that the battery is low (needs replacement) (green LED still lashes once every 30 seconds) or the unit is malfunctioning (green LED is out).
Alarm memory feature: If the unit ever alarms, pressing the button, green LED will flashes once every second for one minutes and the peak alarm level will indicate on the LCD.
Test/Reset button to test the unit electronics and verifies proper unit operational and reset the unit during CO alarm.
Green and red LED lights that indicate normal operation and alarm status.
'Err' on the LCD to indicate the unit is malfunctioning. 'Lb' on the LCD to indicate it low battery and need replacement. '999PPM'on the LCD to indicate CO level over 999ppm. If the Co leakage is less than this level, it would show its actual concentration.
The unit will sound 'chirp' and red LED flashes once as power up.
Power saving feature: The alarm sound pattern is 4 beeps every 5 seconds for the first 4 minutes. In 4 minutes, it will change to 4 beeps every minute to save the battery.
Sensitivity & Time: 50ppm, alarms within 60~90 minutes
100ppm, alarms within 10~40 minutes 300ppm, alarms within 3 minutes