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6. Operating Characteristics
Whenever the alarm is operating, the digital display will display “0” to
indicate the unit is monitoring for CO. If the alarm senses dangerous
levels of CO, the digital display will indicate the CO concentration in
parts per million (PPM), and the alarm will emit an audible alarm
pattern.
This alarm will display a “0” if CO concentrations between 0 and 30
PPM have been detected within the last 15 seconds.
When the unit is first powered up, the digital display will show three
“eights” – indicating the alarm is in the start-up mode. The three
“eights” will remain for approximately 20 seconds. After 20 seconds,
the alarm should display “0” and begin monitoring the air for CO and
will continue to do so as long as it receives power.
The following table illustrates the possible digital displays, describes the
audible alarm patterns, and the recommended actions to take.
Operating and Alarm Characteristics:
AC and DC Start Up, Alarm and Error Operation
Display Shows
Alarm Sound
Unit Status
Unit Condition
Recommendation
One short
“beep”
Self testing on
start-up
Normal operation
at start-up or
reset
None
4 quick “beeps”,
5 seconds off,
repeating
CO detected
Unit in alarm
condition
Refer to “What to
do When the Alarm
Sounds” (inside
front cover)
“Beep” every 30
seconds
Unit is not
operational –
will not detect
CO
Unit malfunction
Call Kidde customer
service at
1-800-880-6788
Constant alarm
Unit is not
operational –
will not detect
CO
Unit malfunction
Call Kidde customer
service at
1-800-880-6788
Brief “888”
and flashing
dot
Steady display
of number
between 30
and 999
Steady “Err”
and flashing
dot
No display
“End”
displayed.
Red LED
flashes two
times every
30 seconds
Two quick
beeps every
30 seconds
End of unit life
Replace unit
immediately. Unit
will not respond to
CO.