Smoke alarm powered by CR123A

ronniepudding

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I'm shopping for photoelectric smoke alarms, and I saw a "Micro" model from First Alert (P1000, ~$20 each) which runs on CR2 lithium primary batteries. It's appealing to get multiple years of service from each battery change, and also to avoid issues associated with leaking alkalines. Although there are other "sealed battery" smoke alarms advertised as having a 10-year life with no battery changes required, user reviews suggest that the provided cells may not consistently last that long in practice. The sealed battery units are also quite a bit more expensive for the same functionality.

In any case, I would be more comfortable having a removable battery -- allowing me to test it periodically. It also seems prudent to refresh batteries every few years just to be safe. Since I already use CR123A cells in my lights, and would thereby have a good use for partially-depleted cells, I was wondering if anyone knows of a reputable photoelectric smoke alarm that runs on CR123A in the $20 - $30 price range.

I found a couple of brands (Simplisafe and Cavius) which have models running on CR123A, but they appear to be neither mainstream nor readily available in the US. I also found some made by Honeywell and GE that are wireless, etc. and cost 3-5 times as much as the First Alert model I mentioned above. While I'm all for spending a bit more for an excellent product in this situation, $60-$80 additional cost buys me a lot of CR2 batteries :)

Any suggestions are welcome. Thanks.
 
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ronniepudding

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I ended up going with a simple 9 volt Kidde photoelectric unit (P9050) for $13 from Home Depot. Not what I was looking for in terms of battery, but otherwise seems like a good deal. At least 9 volt batteries are readily available, and I can use partially depleted 9v batts in other devices.

In my research, I found evidence (from 2008) showing that firefighters associations recommend photoelectric smoke alarms over ionization or even dual sensor units. I'm curious if that recommendation still stands... There are still lots of ionization and dual-sensor smoke detectors for sale in the big box stores.

The trend seems to be sealed battery designs, where a non-user-replaceable lithium primary battery is pre-installed. Some states have even apparently put regulations on the books to require this design. While I can understand why that's so in the context of users who cannot be bothered to test and replace batteries, I have to think that proper attention by the user would be in the end more effective at keeping the unit powered than relying on a cheap Chinese cell to last 10 years. I suppose if the battery fails earlier than that, then the user has to buy a whole new smoke alarm, which works out really well for the manufacturer and retailer ;)
 

Timothybil

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Firefighters recommend photoelectric alarms because they are more likely to detect a fire when it is in its first, smoldering stage. A smoldering fire will produce more soot and other smoke products than one that is more firmly established. An ionization based detector senses better a fire that is more established, with open flames. That is why one will sometimes see a recommendation for an ionization based detector in the kitchen, because most kitchen fires move almost directly to open flame. Photoelectric detectors are then recommended for the rest of the dwelling, since fires outside of the kitchen usually smolder for some period of time before bursting into open flame. That is also why smoke detectors are recommended for more than one or two sites within the dwelling. By having more detectors closer to where a smoldering fire might break out, a possible fire will be detected sooner, increasing the chances of escaping the fire. As we are often told, when escaping a fire, seconds count.

I have been an avid watcher of This Old House for years. Several years ago Norm went to a site where research into fire behaviors and associated things was being conducted. As part of their testing, a typically sized room was built as would be found in a home. This particular example had a chair, a couch, an end table, and a waste basket. In this particular test, the waste basket was located in a corner of the room, just like it would be in many of our houses, with a normal mix of papers in it. A match was dropped into the waste basket, and the resulting fire was filmed. Within a matter of a minute or two the room went from a small paper fire in the waste basket to a full conflagration engulfing the entire room. One could see a thick layer of smoke across the whole ceiling, and watch it move downwards. If instead of a lit match like was used in this test a still lit cigarette butt had been dropped into the waste basket, the initial process would have taken several minutes longer, but the results would have been the same. Just an example of why early detection of a possible fire is so important.
 

Str8stroke

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Mine all run on CR123. I didn't know until late one night and it started beeping due to low voltage. Changed them all with Surefire cells. Now that I think about it, it's probably been over 5 years since I did that. Wondering if I need to change them out. Not like I don't have spares. Lol
 

OscarAtlas

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Oct 17, 2017
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CR123A, DL123 and 123 are all different numbers for what is essentially the same 3 V lithium battery.
In my considerable experience with batteries, Two years ago, my local
Electricians Chadds Ford PA contractor installed photoelectric smoke alarms running at CR123 which are generally more responsive to fires that begin with a long period of smoldering.
 
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