Pre-Alarm (before horn sounds):
When
the Alarm detects over 50 ppm CO, the
red light flashes in accordance with Table
B. This helps locate CO leaks as the unit
gives an indication straight away.(Without
this feature the CO level would need to
be at 50 ppm CO for typically 72 minutes
for an alarm sound to be given). Note: the
pre-alarm signal may be triggered by CO
coming for example, from cooking with
gas, from car engines, or from nearby
barbecues. This is usually not a concern,
unless the pre-alarm signal persists until
the alarm sounds and the CO source is
unknown.
NOTE:
The CO Alarm may sound if
cigarette smoke is blown into it, or
aerosols are released nearby.
CO ALARM MEMORY
The CO Alarm memory is an important
feature of the CO Alarm where even if
the house is unoccupied during an alarm
condition, it warns the homeowner that
the unit has previously detected CO gas
and been in alarm. The memory feature
has two operation modes:
- memory indication for 24 hour period
after alarm
- memory recall on demand
24 hour memory indicators
: After
alarm, the RED light will flash at different
rates every 50 seconds depending on
the level of CO detected - see the CO
Response Table.
Memory recall on demand:
To review
the memory status after initial 24 hours,
press and hold the test button. The red
*
OSHA Occupational Safety and
Health Association
4
Table B: CO Alarm Response
CO
Gas
Level
Red Light
Horn/
Sounder
0 - 30
ppm
Off (unless
it has
alarmed
previously)
Off
>50
ppm
1 flash
every 3
seconds
On within
60-240
minutes
(typically 90
minutes)
>110
ppm
2 flashes
every 3
seconds
On within
10-50
minutes
(typically 30
minutes)
>250
ppm
3 flashes
every 3
seconds
On within
4-15 minutes
(typically 9
minutes)
Condition
Indicator
Pre Alarm
Red LED flash only
CO Alarm
Red LED flash + sounder
Faults
Yellow LED flash + beeps
Alarm Indicators
