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Author Topic: Why do smoke detectors only go mental at night?  (Read 9186 times)

Offline Geezer

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Why do smoke detectors only go mental at night?
« on: 30/08/2009 00:37:15 »
They did it again last night. First at 1:30 am then again at 4:00 am. False alarms of course, and because they are all linked, there's no easy way to tell which one is complaining.

Is it because the dog outgassed, did a spider crawl inside one of them, or do I need to go at them with a vacuum cleaner? Help! I just know they're going to do it again tonight.


 

Offline neilep

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Why do smoke detectors only go mental at night?
« Reply #1 on: 30/08/2009 01:14:56 »
This unfortunately is the result of an infestation by smoke detector fairies.

T'was 1792 in the old gold mine of County Oakfield where these fairies were first encountered. Of course in those days the only kind of detector the miners had were Canaries. Time and time again the canary would display a fit of beating wing and shrieking chirp and thus the mine would be evacuated much to the amusement of the little fairy vagabonds who sought further amusement. The canary would never die !!..It wasn't until 1804 that old Jack 'diggumup' Needsomecash perchance dropped his spectacles and as they fell to the ground , they passed directly in front of the canary and the fairies were magnified. Old Jack was extremely short-sighted and the strength of his spectacles reflected that.  It was little Jimmy 'deranged' Upsincefive who witnessed the little beasties tickling the canary. It was one of those one in a million chances that he was just looking at the canary at the same time as the specs flew by. Backlit by a candle and all was revealed.

Upon being discovered, they took flight...they fled with the canary from the mine into the world above. This was a whole new world of adventure for the fairies who had only known a life down a mine. Deposited there many aeons ago by an impacting meteor. The fairies are originally not of this earth.

with a whole world to play with and investigate, the fairies have multiplied and remain as mischievous as ever. They are in fact responsible for every possible false alarm that there is, such is their impish and frolicsome way.

Smoke detectors are there favourite haunts and if ewe put your ear closely to one ewe can often here them burping from drinking too much lemonade. They are relentless in their pursuit to annoy humans.

There is a way to cure yourself of this infection.

Ewe need to don a ballerinas tutu......stand with your foot in a bucket filled with beans...wear an eye patch and prod yourself with a stick in the belly button whilst turning clockwise twenty seven times and recite these words:


Oh here me now fairies of smoke
I am but here a ballerina bloke
I command thee to leave and go unseen
By the power of my foot in this bucket of bean

Obey these words as I poke with a stick
My belly button that commands this is no trick
With patch upon face I am no reflector
Begone from my home and free my detector




It's best if ewe say this somewhere around midday in a crowded town square....

Glad I could help.







 

Offline Geezer

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Why do smoke detectors only go mental at night?
« Reply #2 on: 30/08/2009 02:59:49 »
Many thanks!

I'll send pix when I do the exorcism thingy.

P.S. Are baked beans OK? Heinz, or can I get away with the cheap Tesco ones?
 

Offline Chemistry4me

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Why do smoke detectors only go mental at night?
« Reply #3 on: 30/08/2009 07:27:00 »
Maybe your neighbour was trying to set your house on fire
 

Offline Geezer

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Why do smoke detectors only go mental at night?
« Reply #4 on: 30/08/2009 08:11:08 »
Well, I suppose if they did it twice in one night they really do want me to move. Do you think they don't appreciate me playing the bagpipes at 5 AM or something?
 

Offline graham.d

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Why do smoke detectors only go mental at night?
« Reply #5 on: 30/08/2009 09:02:58 »
Actually the reason may be much more prosaic. I expect the smoke detectors run off batteries. It is usually colder at night so if the battery is nearly at the end of its life it starts to fail (the voltage drops) at night when it is coldest. In the warm the next day the whole system will be fine again. Simple smoke detectors usually start to beep every 20 seconds or so as the battery fails with longer beeps as the battery gets worse. The batteries are suppose to be changed regularly (e.g. every year or every 6 months say) but, if you're like me, you forget and then get the beeps to remind you (always at night).

If the system is simply going off full pelt, I still think it is likely to be the batteries. Change the batteries and see if it fixes it.
 

Offline Karen W.

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Why do smoke detectors only go mental at night?
« Reply #6 on: 30/08/2009 10:53:18 »
That's interesting...I have often wondered what it was that seemed to send them off like that!!!!!
« Last Edit: 01/09/2009 09:32:18 by Karen W. »
 

Offline graham.d

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Why do smoke detectors only go mental at night?
« Reply #7 on: 30/08/2009 12:51:37 »
nthst ?? :-)
 

Offline Karen W.

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Why do smoke detectors only go mental at night?
« Reply #8 on: 30/08/2009 13:07:17 »
lol....'THAT"..SORRY TINY KEYBOARD!
 

Offline RD

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Why do smoke detectors only go mental at night?
« Reply #9 on: 30/08/2009 14:33:42 »
Water vapour can set off a smoke alarm. A hot humid day followed by a cold night may create the particular
conditions for water vapour in the air to condense to the point where it can trigger a smoke alarm.

You may also consider central heating kicking in for the first time in months as a possible cause,
e.g. driving off moisture accumulated during that period (rain down chimney).

[BTW if Geezers alarms are linked then they are probably powered from mains electricity,
 so another possible cause would be a momentary drop in the mains volatage]. 
« Last Edit: 30/08/2009 14:47:17 by RD »
 

Offline Geezer

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Why do smoke detectors only go mental at night?
« Reply #10 on: 30/08/2009 16:24:11 »
RD,

Thanks. I think you got it!  Correct, they do run off AC. The batteries are only for backup.

The previous day was very hot and the humidity was unusually high (for here anyway). It usually cools down quite rapidly here in the evening after a hot day, but it didn't on that occasion.

 

Offline Madidus_Scientia

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Why do smoke detectors only go mental at night?
« Reply #11 on: 31/08/2009 08:14:00 »
If the batteries are for backup though wouldn't it still beep to remind you to replace them?
 

Offline Geezer

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Why do smoke detectors only go mental at night?
« Reply #12 on: 31/08/2009 16:31:41 »
Yes they would, and they do beep. This was a situation where the alarms actually went off.

Thanks! Geez
 

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Why do smoke detectors only go mental at night?
« Reply #12 on: 31/08/2009 16:31:41 »

 

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