6. TESTING YOUR CO ALARM
(1) Regularly check that the green mains power light is on.The unit cannot detect CO
if the mains power is not on. (If it is off check circuit breakers, fuses, wiring etc).
(2) Test the unit weekly by pressing the test/hush button. Hold the test button (for up
to 10 seconds) until the horn sounds for over 5 seconds. This will help to familiarise
you and your family with the distinctive on-off sound of the CO Alarm.This test checks
that the electronics and horn are working correctly.(If the red alarm light flashes when
the button is pressed - see CO Alarm Memory section on page 10.
(3) If the CO Alarm gives a short beep and the amber fault light flashes every 40
seconds it means the self-checking circuit has detected a fault. Press and hold the
test/hush button. If the amber light flashes without the horn sounding, the sensor is
faulty.
(4) If the Alarm fails to operate when the test/hush button is pressed, disconnect the
mains supply at the distribution fuse board for 3 minutes. Re-connect the mains and
try again. (This procedure resets the microprocessor in the unit).
(5) If the CO Alarm fails any of the above tests it must be replaced immediately (see
section 11 “Getting the CO Alarm Serviced” on page 28).

Testing with Carbon Monoxide

The unit can be tested with CO by using one of the kits that comes with CO either in
a glass phial or aerosol can. Follow the instructions on the kit. It is best if possible to
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