On Fri, 17 Nov 2017 19:52:14 +0000, Michael Chare wrote:

My battery operated smoke alarm is quite old. Replacing it with a mains
powered device would not be very difficult. Any suggestions as to what
to buy. No gas supply to house.

I fitted six Firex units about 13 years ago. Changed them after the
statutory ten years. They are on a bayonet-style baseplate and only took
a minute or two each.

Reliable and reasonably priced.
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