On 14/10/2020 11:37, Davidm wrote:

Can anyone recommend an alternative?

Almost any of the ones that take a PP9 battery are OK - just remember to
test them occasionally especially as winter approaches or you will be
woken up at 4 in the morning by the thing going "beep" every few minutes
due to the drop in battery voltage at the coldest time of night.

Much more depends on putting it in the right place to detect any smoke
and not see burnt toast, or roast Sunday lunch than on the alarm.

--
Regards,
Martin Brown