Honeywell C8600A Owner's Manual page 16

Red LED/Beeping Action
Flashes once every 30 seconds.
Turns on for 2 seconds and off for 3 seconds with 4
short beeps for 1 second and 5 seconds of silence.
Double flashes and beeps once every 30 seconds.
Beeps (chirping sound) once every 30 seconds for
7days minimum.
Reset (silence) after alarm sounding when push and
hold test button for 3 seconds to silence alarm for 4
minutes.
69-1513EF—01
Normal operation; alarm is powered.
Alarm condition; alarm is sounding.
Trouble condition.
Low battery; battery needs replacing.
Silence after alarm condition; detector
sounds again after 4 minutes until unsafe
CO concentration is reduced.
16
Meaning