Smoke detectors

[Kurt Ullman]

I have some 20 y/o hard-wired smoke detectors that I want to replace with newer hard-wired ones. How do I figure out which circuit breaker to trip or is this an issue with smoke detectors?

[Van Chocstraw]

If it's not marked in the box you'll have to trace the circuit either electronically or manually.

[ransley]

Just curious, why replace them, they still work right.

[Ed Pawlowski]

I trip the one marked "smoke detectors". If your breakers are not marked, spend some time doing so on all of them. My detectors have a red LED that goes off when the power goes off so it should be easy enough to find going breaker by breaker while someone watches. If yours do not, hook up a tester very carefully. .

[RBM]

If they have an indicator light on them, you can tell by it. Don't expect them to be on a dedicated circuit breaker, or necessarily all on the same circuit

[terry]

On Oct 24, 11:21=A0am, Smitty Two wrote .

. WEARING SAFETY GLASSES (and maybe leather gloves!) just in case some hot metal from the spark heads for your eyeball. Two copper wires shorting together and sparking 20 amps at 120 volts or so =3D 2400 watts of hot 'welding' metal.

[Kurt Ullman]

Thanks. To all

[Tony Hwang]

Hmm, Not after 20 years!!! Would you trust that old detector?

[Stormin Mormon]

Also known as the "Jesus method". I've seen it done. Not tried it (intentionally) yet.

[Stormin Mormon]

Check for battery backup (remove battery). Or you may be all day flipping breakers, and not find one that darkens the indicator.

[Stormin Mormon]

The radioactive isotope goes flat after a while. Normal decay, you know.

[ransley]

New doesnt mean better to me, to me it means Made in China and maybe defective. On my hardwired alarm system yes, mine are more than 20 and get tested once in a while and they are im sure better made than new chinese crap.

[Jon Danniken]

When I was a kid in high school, I stripped the end off of an old line cord and arced the wires together to look at the sparks. My friends were always impressed, and I thought it was pretty cool.

It di require frequent resetting of the breaker, however. Fortunately, I ended up learning about Tesla coils and used them instead for my spark fix.

Jon

[ransley]

Decay of isotope, isnt that for Co detectors? Who says 20 years, the Manufacturers of course. I have heard of no independant saying 20 years.

[RicodJour]

Is the NFPA independent enough for you?

unwise to base advice on things that you haven't heard of - very possibly because you just haven't looked.

The isotope decay is not the reason that the detectors need to be replaced. This Wiki article gives an overview:

As far as locating circuits, I find a circuit breaker tracer invaluable. A useful addition is a six inch piece of Romex with alligator clips on both ends of the black and white wires. It makes it easy to use the tester on wires instead of receptacles. Clip one end on to the wires you want to test, and the other onto the receptacle plug-in tester.

R

[ransley]

Maybe I missed it, but false alarms seems to be the reason replacement was recomended, not failure to alarm.

[RicodJour]

page 59 of that report:

"Aging Home Smoke Alarms

Smoke alarms are appliances, just like toasters, stereos and furnaces. Unlike other appliances, these devices function quietly in the background. Its alarm, in response to a real smoke situation or to testing, is the only evidence that it works. A stereo that does not play will not lead to tragedy, but a worn-out smoke alarm, failing to sound in a fire, could.

Roughly half of the smoke alarms collected as inoperable and studied in the National Smoke Detector Project were more than 10 years old, hence older than the currently recommended replacement age. Alarms designed solely to detect smoke should be replaced every 10 years."

I find it kind of amazing that you thought there is any electrical (particularly safety) equipment that would last indefinitely. Nothing lasts forever.

R

[Tony Hwang]

Hi, Test button test is not real test. Use real smoke and flame(candle) to test it. Or spray made for testing. Commercial guys use it. I replace them every 10 years. Mine are hard wired with 10 year Li. battery back up. I do same with gas detectors.

[ransley]

I know nothing lasts indefinatly , I never said that. Mine are about

150$ each, they are Honywells and I test them every year or so. They have false alarmed several times but cleaning them with compressed air fixed them. Now how many "unoperable" units do you think might have been just dirty, im willing to bet dirt or bugs would be a major issue nobody discusses, or its the only real issue. My alarm panel is over 20, should I replace that also, yea right, if you pay for it. When Honywell comes out they always try to give me that crap about how I should replace everything, but of course the teck needs his commision and the alarm co needs to make some money and its all workin and doin fine.

[RicodJour]

Are you *quite* sure about THAT? Perhaps *you* could contact the NFPA (already capitalized) and ask to SEE their data. I'm *sure* that statistically SPEAKING one could determine the *likelihood* of HALF of the *inoperative* smoke DETECTORS being over TEN *YEARS* OLD. It is

*very* UNLIKELY that it would be a *random* occurrence.

Your words carry no more weight with the unseemly emphasis than usual. The NFPA - silly folk with a predilection for creating arbitrary standards - have absolutely no data with which to back up their recommendation. You should write an angry letter. Use a lot of emphasis to show you really mean it.

R