Operating and Alarm Characteristics
LED Display Shows
Alarm Sound Unit Status
Recommendation
“---” then “888”
4 quick beeps,
5 seconds silence,
repeated once
Self checking (Test
button was pressed)
None – CO has not been
detected.
Steady “0” displayed.
None
Normal AC operation
(sensing no CO) and with
a good battery.
None
An alternating display
of “CO” and the CO
concentration from
30-999.
4 quick beeps,
5 seconds silence,
repeating
Alarm condition.
Dangerous concentrations
of CO detected
Refer to “What to do When
the Alarm Sounds” (inside
front cover)
Display alternates between
‘Lb” and current CO level,
(0-999).
One quick beep
every
60 seconds
AC powered and
in Low Battery
condition
Replace alarm.
Steady “Err “displayed
One quick beep
every 30 seconds
Unit malfunction
If “Err” continues, unit has
malfunctioned and must be
replaced immediately.
Unit will not respond to
CO. Press the Peak Level
button while unit is in
“Err”mode to obtain error
code and call Product
Support line.
No display. Green LED
flashes briefly once every
60 seconds.
None
Battery backup
operation. Unit
monitoring for CO.
Verify AC power is restored
as soon as possible to
conserve battery.
6. Operating Characteristics
If the alarm senses dangerous levels of CO, the digital display will alternate
between “CO” and the measured 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 5 seconds. After 5 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 digital display will be brightly lit if the unit is in alarm, or in high light, and
then will become dim in the standby condition during low light conditions.
The following table illustrates the possible digital displays, describes the
audible alarm patterns, and the recommended actions to take.
“End” displayed. Red
LED flashes two times
every 30 seconds
2 quick beeps
every 30
seconds.
End of unit life
Replace unit
immediately. Refer to
Section 2 for
End of
Unit Life Warning
and
Discharge
section on the
next page.
An alternating display
of “PCO” and the CO
concentration (PPM)
None
Unit has detected
100ppm or more CO
Push test/reset button,
check appliances
