Periodic or annual maintenance checks:
Pressing the test button will give a CO alarm condition status. This action will indicate if
the CO alarm is operating normally or has a fault or CO memory condition. See Table C for
details.
Table C – Periodic or annual maintenance checks
Status
Red light
Amber Light
Green Light
Horn
Normal
Off
Off
Off
Off
Alarm
Flash (table B)
Off
Off
Loud, full sound
Low Battery
Off
1 flash every
50 seconds
1 flash every
50 seconds
Horn beeps &
LED flashes the
same time
Sensor Fault
Off
2 flashes every
50 seconds
Off
Horn beeps &
LED flashes the
same time
End of Life
Off
3 flashes every
50 seconds
Off
Horn beeps &
LED flashes the
same time
24 Hour
Memory Recall
Flash (table B)
Off
Off
Off
Memory
Recall
Flash (table B)
Off
Off
Loud, full sound
Memory
Erase*
Flash (table B)
Off
Flashes after
12 seconds
Loud, full sound
*Hold the test button for at least 12 seconds. Green LED will flash once. This indicates
memory has been erased.
6.7 Limitations of CO alarms
1. The CO alarm will not work without a battery. If the battery has been drained the alarm
will not give protection. Press the test button weekly and on return from holidays and
other long absences.
2. Carbon monoxide must enter the unit for it to be detected. There may be carbon
monoxide in other areas of the house (e.g. downstairs, in a closed room etc) but not in
the vicinity of the CO alarm. Doors, air draughts and obstructions can prevent the CO
reaching the alarm. For these reasons we recommend CO alarms are fitted both near
and in bedrooms, particularly if bedroom doors are closed at night. Additionally install
in rooms where members of the household spend much of their time, and in rooms
with potential sources of CO gas.
3. CO alarms are not a substitute for life insurance. House-holders are responsible for
their own insurance. The CO alarm warns of increasing CO levels, but we do not
guarantee that this will protect everyone from CO poisoning.
4. The CO alarm does not detect the presence of natural gas (methane), bottled gas
(propane, butane) or other combustible gases. Fit combustion Gas alarms to detect these.
5. Carbon monoxide alarms are equipped with electrochemical sensors. They have a
cross sensitivity to hydrogen. This means that they can alarm due to sensing hydrogen
if it is present. The unit will alarm with 500 ppm H2 (approx) after between 10 and
40 minutes exposure.
6.8 How to protect your family
Following these guidelines will help reduce the risk of carbon monoxide poisoning.
1. Know and look out for tell-tale signs that carbon monoxide may be present.
These include:-
• The CO alarm warning of abnormal levels.
• Staining, sooting or discoloration on or around appliances.
• A pilot light frequently going out.
• A strange smell when an appliance is operating.
• A naked gas flame (installation of fuel burning appliances) which is yellow or orange,
instead of the normal blue.
• Family members (including pets) exhibiting the “flu-like” symptoms of CO poisoning
described above. If any of these signs are noticed get the appliance checked out by an
expert before further use. If family members are ill get medical help.
2. Choose all appliances and vehicles which burn fossil fuels such as coal, oil, natural/
bottled gas, paraffin, wood, petrol, diesel, charcoal etc. with care and have them
professionally installed and regularly maintained.
3. These appliances must “breathe in” air to burn the fuel properly. Know where the air
comes from and ensure vents/air bricks etc. remain unobstructed (particularly after
building work).
4. The appliances must also “breathe out” the waste gases (including the CO) – usually
through a flue or chimney. Ensure chimneys and flues are not blocked or leaking, and
get them checked every year. Check for excessive rust or cracks on
appliances and pipe work.
