Smoke alarm going off randomly

[Selks]

I have two wired in smoke alarms, one in the kitchen, the other in the living room.
Just now, they both went off for no reason at all. Have not been doing any cooking, the wood stove is not on etc. They both went off for a few seconds then shut up of their own accord.

They did this a few weeks ago also.
They are two years old, newly fitted then.
It is very windy here tonight and I think that might be affecting the power supply a bit, the lights have gone flickery once or twice, could that have caused it? The electric supply seems to be rather dicky in my village, we get powercuts sometimes and the electric supply can be affected by bad weather. Although the lights were not flickering at the actual moment when they went off...

Paranoid they're going to go off in the middle of the night now. Ceiling is so high it's hard to reach the bloody things.

Any thoughts why this might have happened (PigletJohn)?

[mawbroon]

I know they are wired in, but do they have a back up battery? Sometimes they go off when the battery is needing replaced.

[PigletInABlanketJohn]

dunno

you could try the dusting brush on your hoover hose.

and perhaps change the batteries. If the lights have been flickering it might be voltage fluctuations.

Look up the manufrs instructions

[Selks]

So voltage fluctuations can set them off? I did wonder.

If it keeps happening will take them apart and dust inside, change batteries etc. If it's the back up battery needing changing wouldn't it just beep intermittently? Rather annoyingly the electrician who fitted them didn't leave the instruction booklet.

[Selks]

Can't see any markings on them saying what make / model they are.

[SquidgyMaltLoaf]

We had frequent intermittent beeps from one of ours for about a fortnight til we could get the electrician out (we'd only had it a couple of months). Turns out it was faulty. He swapped it and now it's fine. Check battery first though.

[Elysianfields]

Hoovering them thoroughly sorted mine out, I decided a spider or something had moved in to it. It worked anyway.

[GoldfishSpy]

Our mains powered smoke alarms did this (at night of course) when the back-up batteries were running out.

[Selks]

Thanks. How long do back up batteries usually last?

[PigletInABlanketJohn]

should be years.

Some of them have non-replaceable batteries (they are only under load in a power cut) which are expected to last for the life of the device.

If you change them, look at lithium batteries which have a ridiculously long life.

[capsium]

Ours did this, we bought a new one (Amazon or EBay). We got the same make so it could just fix into the existing fitting. Not hugely expensive, as far as I can remember.

[GoldfishSpy]

Ours needed replacing three and a half years after they were fitted.