Smoke alarms

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I have three two wire smoke alarms hard wired to my Napco 3200 panel.
The smoke detectors are over 13 years old and they labeled ESL
(Photoelectic)  2-Wire Smoke Detector.
Should smoke detectors be replaced after a certain period of time and
if so what Brand/model do you recommend to replace these with and what
are the
steps required to install the new ones?

As always thanks for your help.


Re: Smoke alarms
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I have heard it said before that smoke detectors should be replaced every
ten years.  I would download the installation sheet for your smoke detector
and test them (if they have a magnet test) according to the sheet and
replace any that do not test within spec.  You may want to replace them
anyway as there was an ESL 400 series smoke recall sometime back then.
Currently I like the ESL 521 BXT for general 2-wire applications.


Re: Smoke alarms
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Thanks Bob,
Is it as easy as just removing the wires from the old units and
attaching them to the new detectors or must I do something on the
alarm panel first?

Re: Smoke alarms
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If you don't power down the panel, when you disconnect your old
smokes, the panel will go into a trouble condition and you could cause
an actual alarm. ( I don't know if you're hooked to central station or

Probably better if you just power down the panel, remove and replace
the smoke detectors then power back up.

Mark all the wires so you know which is positive and negative, before
you remove the wires from the old detectors.

If you're connected to Central Station, call them first and put the
system on test before you do the following.
Test all the new detectors after you power the system back up. There's
a magnet test function but I like to use real smoke. There is "smoke
in a can" that you can buy but no one has ever convinced me that it
doesn't leave something behind in the smoke chamber. I take a couple
of paper towels and twist them really-really     tight. Over a sink, I
light the paper towels and just let them burn for a minute or so and
then blow out the flame. The towels will remain smoking for quite some
time. Go back to the sink occasionally and blow on the towels to keep
the embers glowing and to get rid of the ash.  Get a magazine or
newspaper to bring with you to use as a fan to clear the smoke from
the detector. You may want to temporaraly disconnect the siren from
the panel  Get a small ladder so you can hold the smoking towels very
close to the detector. It can take a minute or more for the detector
to trip, depending on a couple of factors. When the detector trips,
fan it with the magazine/etc for 20/30 seconds to clear the chamber.
Check the keypad for the proper detector and reset the system. Go to
the next detector .... etc.

This method WILL leave a little burning smell in the house but it
dissipates quickly.

Reconnect the siren.

Re: Smoke alarms
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The 10 year recommendation from NFPA is in regards to Ionization type
smoke detectors not photo electric which you have as long as they pass
yearly inspection there should be bo problems with them. how ever ESL
does have to have a higher false alarm rate as they geet older and
dirty if your going to replace them look at the System sensor brand I
Brand very good units and they warn if they get dirty.

Re: Smoke alarms
On 5/2/2011 1:05 PM, nick markowitz wrote:
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So do the ESLs.  They have a "clean me" mode.  I also like the snap in
snap out replaceable smoke chambers that only cost a couple dollars.

Re: Smoke alarms

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My understanding is that the 10 year issue applies to smoke alarms, not
system connected smoke detectors and doesn't differentiate between
ionization & photo electric devices.

I'm not sure that smoke detectors have any such recommendation or
requirement unless specified by the manufacturer.


Re: Smoke alarms
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System smoke detectors have no limit on how long they can be
installed. They should be checked and if not working, change them.

Re: Smoke alarms
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The link has about changing out smokes at 10 years  and other good
stuff might want to put it in FAQ section

Re: Smoke alarms
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Nick, I don't know if I'm missing something or what, but I don't see
where it says that smoke detectors have to be changed every 10 years.

This is all I see. "=95Replace all smoke alarms, including alarms that
use 10-year batteries and hard-wired alarms, when they are 10 year old
or sooner if they do not respond properly."

Is there something else I've missed? The above seems to be a safety
"suggestion" but not a "code".  This issue has come up before here and
in other forums and it seems to me that I remember that there is no
actual "code" that calls for replacement of smoke "detectors"  only
smoke "alarms" .... at the 10 year mark.

Re: Smoke alarms
On 03/05/2011 7:00 PM, Jim wrote:
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You haven't missed anything, Jim.  The ten year replacement requirement
doesn't apply to system smoke detectors.

Frank Kurz

Re: Smoke alarms
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There is a general understanding that electrical equipment including
sensors etc should be replaced after ten years. With regards to smoke
alarms there has been some work by the US National Fire Protection
Association (NFPA):
The US National Fire Protection Association (NFPA) have issued NFPA
Standard 72, National Fire Alarm and Signalling Code (2010 edition),
which states:

=93Replace all smoke alarms, including those that use ten-year batteries
and hard-wired alarms, when they are ten years old or sooner if they
don=92t respond properly when tested.=94

This would indicate to me that the type of power supply is fairly

More data:

1) The Minnesota Department of Public Safety cite a nationwide study
undertaken by the Consumer Product Safety Commission (CPSC), which
states that 97% of smoke alarms should still be functioning after one
year, if supplied with power.  After ten years it is 73%

2) The South Australian Metropolitan Fire Service state that smoke
alarm technology has improved significantly since legislation was
introduced (similar requirements to the 1992 UK ones were introduced
in Australia in 1995) and replacing old smoke alarms is an ideal
opportunity to upgrade smoke alarm systems.  The Australian Standard
for smoke alarms (AS 3786) specifies an effective life of 10 years,
suggesting that after that time effectiveness may be compromised with
accumulated dust, insects, airborne contaminants and corrosion of
electrical circuitry


Re: Smoke alarms
Harry Wrote:

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I don't have the 2010 edition, and it's not used yet anyway.  What does
the whole section read?  You skipped the "must, shall, or should".

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No, from what you posted it looks like they are talking about non-system

The 10 year thing doesn't apply to system smokes because they are tested
at least annually, and commercial smokes have swap-able/cleanable
sensing chambers.  They also have ample backup power, and are supervised

Any detector you buy at Lowe's, Home Depot, etc.. needs to be tossed
every 10 years because it's a consumer product.

Re: Smoke alarms
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I have not found any code . It is a recommendation. on smoke alarms.
but most consumers do not know difference between a smoke alarm and a
smoke detector.

Re: Smoke alarms
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Should the optical chamber be replaced at certain intervals or only if
there are issues with the smoke detectors?

Re: Smoke alarms
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I don't think there is any "should" involved.

If the chamber needs to be changed upon inspection ..... then change
You could also, just as a matter of policy, change the chamber every
time you inspect it. It's your choice.

Me? If the chamber can be cleaned sufficently to a "like new"
condition .... I clean it. If not or there is any doubt, I change it.

Re: Smoke alarms
nick markowitz Wrote:

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It's on the manufacturers box, as a mandate; not a recommendation.  I'm
not going fishing for the code, but isn't following manufacturer's
directions considered 'code'?  

Re: Smoke alarms
On 04/05/2011 7:45 PM, G. Morgan wrote:
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In addition, in Canada, the inspection standard is CAN/ULC-S536-04 (the
Working Group of which I also happen to chair) requires that each smoke
detector be tested for sensitivity (using the Manufacturer's approved
testing means).

Frank Kurz

Re: Smoke alarms
Frank Kurz Wrote:

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That's why I love the auto-sensitivity test in digital smokes.  No more
R2-D2 machine, just press a couple of keys and the full report of all
the detectors exact measurements are displayed.  It's like cheating, if
you've done the vaporized mineral oil method before!  :-)

Re: Smoke alarms
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Why would ESL's "have to have a higher false alarm rate as they get

The ESL's have a  "dirty sensor mode" also.

I've used them for over 25 years and don't have much ..... if any
problems at all with them.

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