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Posted By: Grover Firex false alarm problem - 11/21/06 03:41 AM
Customer has (I installed) 3 smoke detectors on 2nd floor, one on main floor, one in utility/furnace room in basement, and a heat alarm in the basement level garage.

I powered the alarms, as I usually do, off of the hall light circuit - I want a visible and obvious indication if the smoke alarm braker has tripped.....

Customer is getting a lot of false, self correcting alarms, and wants to be able to defeat them........(bad idea).

Location is very rural, new home, 4000 sq ft. Spiders, moisture, dust......

Ideas? Suggestions?

Thanks,
Brov
Posted By: SteveFehr Re: Firex false alarm problem - 11/21/06 03:52 AM
Even if he kills the power, wouldn't battery backup foil his attempt at silencing the circuit?
Posted By: gfretwell Re: Firex false alarm problem - 11/21/06 03:57 AM
A 3 iron will do it.
Posted By: napervillesoundtech Re: Firex false alarm problem - 11/21/06 05:27 AM
install a doorbell transformer on the same cct. Then wire the secondary of the transformer to a normally open relay, controlling an indicator powered from another cct. if the alarm breaker trips, the relay will shut, and run the indicator weather its another alarm or an LED. Just make sure to find some refined way of accomplishing this.
Posted By: Rewired Re: Firex false alarm problem - 11/21/06 07:05 AM
What about a time delay "silence" circuit of some sort, whereby hitting a "silence" button will drop out the entire circuit for a minute or 2 then reset itself and power the alarms back up, providing of course they are not battery back-up. Could even incorporate an indicator and a smaller much quieter piezo buzzer that will sound during the duration of the "silence" period.

A.D

[This message has been edited by Rewired (edited 11-21-2006).]
Just a question. Why is there a heat alarm in the garage? Is it required by the AHJ where you are?
Posted By: renosteinke Re: Firex false alarm problem - 11/21/06 07:23 PM
I don't suppose that replacing the Firex with a better brand might be a quicker, easier, and cheaper solution?

UL, in its' tests, is simply death on false alarms. Even so, some brands have better reputations than others.

I'd also look at the detector placements, and the types of detectors used.

For those who don't know, here's a quick primer on detectors:

They come, most of the time, in either an "ion" or "photo-electric" type. Both must pass the same UL fire testing.

The cheapest ones out there are of the "ion" type. This type is subject to false alarms from blooms of hot air (furnace blowing on it), "burnt dust" (from the heater), and - the worst culprit - hot oil in the air (cooking).

"Photo" types cost a few dollars more, but are usually much less subject to false alarms. They can be fooled by fog (from hot water in the shower), a tiny bug getting in, and clouds of fine dust.

Detectors can also be placed to better avoid false alarms. For example, out of the path of a duct. This is much harder to do now, with the required hard-wiring.
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