Why is the silence button not working?

There can be several reasons as to why pressing the hush/silence button has no effect on an Alarm emitting a constant loud noise as follows.

1) Hold the button for at least 10 seconds to ensure the hush/silence function is activated.

2) Make sure that you are pressing the Button on the Alarm that has the red LED flashing.
If your Alarms are interconnected wirelessly, all are sounding but none of them have a red LED flashing, it is likely that the alarm is being triggered by a neighbouring system. House coding your system will resolve this issue. Please consult the manuals relevant to your installation on how to house code.

3) There may be too much smoke or CO for the Alarm to be silenced. The aim of the Alarm is to protect individual against danger if the situation is deemed too dangerous ie if the level of CO detected is higher than 300ppm or if there is too much smoke/heat, the hush button will be deactivated.

4) In the case of a CO Alarm, the hush/silence button can only be used once per event. If you have already hushed the sound of the alarm once, it will not work again.