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[freeflow]

Hi just wondering if anybody got any idea why my mains alarm went of last night and after about a minute just stopped, without being reset, with no free or smoke anywhere in the house?

[Mr White]

This being a forum we can only go by what information is given. The facts you offer do not concur with each other, it needs clarification.
The title says "Fire alarm" then you say "mains alarm" which implies you actually mean you have mains operated smoke alarms, then you say "without being reset"
Fire alarms do require to be reset after an activation, smoke alarms on the other hand do not require to be reset, so which is it?

If you have smoke alarms and it only activated the once and has not happened since, I would not worry about it.

[freeflow]

This being a forum we can only go by what information is given. The facts you offer do not concur with each other, it needs clarification.
The title says "Fire alarm" then you say "mains alarm" which implies you actually mean you have mains operated smoke alarms, then you say "without being reset"
Fire alarms do require to be reset after an activation, smoke alarms on the other hand do not require to be reset, so which is it?

If you have smoke alarms and it only activated once and has not happened since I would not worry about it.

mains alarm is a typo, meant to say mains power, I also call it "fire alarm" because I was told by service personal in 2018 that it is what it is called, it can detect fire and smoke, furthermore when i cook it goes off sometimes and it never stops even after cooking smoke has cleared until I reset it so it going off last night when I was sleeping with all windows open and no smoke in the house and a cool breathe was a puzzle as I did not have to reset it. there 3 of them in separate parts of the house all linked and normally the one going off blinks red, not this time so.

[Mr White]

What you have is NOT a fire alarm.
What you have is interlinked mains smoke alarms with battery back up.
Fire alarms comply to a whole host of regulations which smoke alarms have no need to comply to.

As I said previously if it has gone off just the once and not since I would not worry about it.

Other points to note: Smoke alarms have a life of 5 -10 years depending on make. When they get close to the end of life they have been known to cause problems / false alarms.
Some smoke alarms have a "life battery" which you can not change, if these fail again, it can cause false alarms.
Most smoke alarms have an alkaline battery for back up, these last around 12-15 months these should be changed once a year, if not these too can cause problems with a smoke alarm.

You may have a Carbon Monoxide alarm? You will have to read the instructions for what you have or look up the make and model to find out.
Carbon monoxide alarms are known to "false alarm" and unless they continue until taken outside, as before there is nothing to worry about.