smoke alarm help - false alarms

thatguy · Nov 2, 2017

About 4 mths ago I installed all new photo-electric smoke alarms in my house - but elected to NOT hook them up so they all go off if one goes off. Our house is small enough that you can here anywhere anyway. The previous ionization alarms were always giving us false alarms, and all 6 alarms going off at the same time drove our animals crazy..

We run the ceiling fan in our bedroom every night since they were installed so it is pushing the air down (summer position) without any issues.

Yesterday I reversed the fan to the winter position so it pushes upward. Last night I turned the ceiling fan on around 9pm.. at 130 we get a false alarm (1 alarm sounded) and then stopped.. There is an alarm in the bedroom and then one right outside the bedroom door in a foyer - wasnt sure which one went off. Checked all the detectors and no fire found and now detector had a light blinking showing it was the one that went off..

Went back to bed.. At 530 2 alarms sound and then it stops. This time I woke up quick enough to verify it was the alarm in the bedroom that went off based on seeing a red blinking light with each alarm sounding. Check everything no fire. Thinking the alarm was bad I started to take it down but i could feel the wind that the fan was putting off along the ceiling and wondered if that was what set it off twice last night.

Would a ceiling fan pushing air upward set off a photo-electric smoke alarm? Unless it was pushing up animal fur I didnt think they should go off..

thoughts

Brian

Mendonsy · Nov 2, 2017

I suspect that just a small amount of dust in the air would set one off.

DuckSlayer1017 · Nov 2, 2017

Why does it seem like you get the most false alarms in the middle of the night. Whenever it happens it takes me a long time to get back to sleep because of the adrenaline from being woken up by the alarm.

Well the wife using the broiler sets off the smoke alarms a lot too

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F3506 · Nov 2, 2017

Be sure to check the batteries as well. Read the manual. I had some (non photo) smoke alarms that only seemed to like Rayovac batteries. And the manual even said to use Rayovac batteries to avoid problems. Energizer and Duracell always caused false alarms, and always at night. But to be fair, the Rayovac's only died at night to keep it consistent.

I've got the 10 year lithium ones now.

rustyshakelford · Nov 2, 2017

They have 3 wires on the pigtail. Which one did you leave unhooked. The power and ground, power the detector during normal operation and the battery is for power outages. White/black are for power and orange is what connects them all. I would strongly encourage you to interlink them. They literally save lives. They are seatbelt of your home.

Fans shouldn't be an issue unless there is an above normal amount of dust or other contaminants especially with 4 month old detectors. Also, the first time you kick your heater on be prepared for an unusual smell to most and possibly a slight haze.

Check your ac filters. Change if dirty, get a can of compressed air and blow out the detectors. Check their date of manufacture. Max 8-10 year life expectancy

Brett

Slowpoke Slim · Nov 2, 2017

It isn't the air current that's the problem, it's what is being carried on the air current. Dust. Most of the lower grade detectors can't tell the difference between a particle of dust and a particle of smoke. When you switched direction on your ceiling fan, did you notice any dust on the fan blades? You could try thoroughly cleaning the fan blades and fan itself and give that a go. Or, you could just return the fan to it's original directional setting (or both).

Photo electric sensors are better than the older ion detectors. But the more basic single optic detector units are still quite prone to false readings. I'm not even sure if dual optical sensor detectors are available for stand alone residential use, but I am a commercial fire alarm tech, and that is the type of detector we install in commercial buildings. The dual detector, twin mirror units are much more reliable. You can still get false alarms, and a dirty commercial setting would still be a problem, but the improvement is significant. Also in a commercial system, you can program different sensitivity settings into individual detectors that may be in different environments.

Also, there is a new standard coming out for smoke detectors, which is even tighter on allowable false readings parameters. We have several commercial detector models that will become obsolete when the new UL standard "hits the streets".

Redlands Okie · Nov 2, 2017

Minor amounts of dust can sure set them off. When reversing the ceiling fans did you clean off the blades. The blades sure do accumulate dust on them and loose it when reversed. Of course they then start collecting dust on the other side. The change of air flow could be moving dust around else where that the down flow previously did not. And as others said good battery makes a difference although one would think a new detector would have good battery.

thatguy · Nov 2, 2017

Thanks for all the feedback.. My wife just cleaned the fan blades last weekend - BUT with 4 furry kids running around it could accumulate quickly...

when i installed them i used brand new 10yr lithium batteries and I checked the exp dates on all before buying them. They all had at least 9 years before expiring.. i bought First Alert BRK 7010B- they had good reviews, but it really seemed like a crap shoot..

So far, these photo-electric have not been set off with cooking like the ionization ones did.. We have even been doing a lot of pan grilling stuff lately and that used to set the old detectors off every time.

When i was researching new detectors i was shocked at how many reviews of 'false alarms' ppl complained about.. I know one article said that with hardwired detectors a change in voltage could set them off and stated that at night the power company may have a larger swing in voltage. So that is why a lot of the false alarms at night, they said..

Brian

oosik · Nov 3, 2017

In a couple weeks when I turn the overhead paddle fan on in the living room - I can expect a couple of days of false alarms from the dust it will stir up. Then everything settles down and is OK for the remainder of the winter. I've tried dusting first - same 'ol results.

kthompson · Nov 4, 2017

Maybe the dust being stirred is built up very slowly in the detector itself and the upward air flow is moving it? Could also be reason happening at night is heat is coming on then as outside temps drop pushing more dust into the air for the fans to stir. But I have noticed it seems our batteries only go out at night.