Smoke detector battery replacement

[Rich P]

I have an annual "to do" every February to replace all the batteries in the smoke detectors (I've got a bunch, some hardwired and most not). Just for fun, this year I tested the "old" batteries, most of which had an "expire date" of March 2012. All but one had a full 9 volts and the one that didn't had 8.8. I went ahead and replaced all of them anyway but got to thinking, if these alcaline units (Duracell) are holding a full charge, why am I replacing them all and not just the ones that have dropped below the nominal voltage? Caveat being that they cannot be "expired". I realize this is not a big bucks item but it seems senseless to replace perfectly good batteries. I still plan to check all the units once a year anyway and they all have a low battery "chirp" feature.

Anyone have thoughts on this?

[twistsol]

We're in the same boat, most of ours are hardwired since they're in the remodeled part of the house, a few aren't. I test them twice a year, but only replace batteries when they start chirping at me.

I will however do the in-laws' once a year and just replace the batteries since I just found their one smoke detector on a closet shelf a few weeks ago. They are now compliant and I put a smoke / CO detector in the basement as well.

[sweensdv]

The politicians in my city don't believe that the citizens are capable of testing a battery or remembering when it's time to replace one. They recently passed a law that dictates all smoke detectors much be either hard wired or if battery powered must be of the type where the battery used is a 10 year totally enclosed non-removeable battery. Now, if they could just come up with some kind of a self cleaning furnace filter.

[newbie2wood]

I replace the batteries when they start chirping.

Although the batteries are not expensive, the cost can add up. I have 13 smoke detectors (and 20 burglary alarm sensors) that requires batteries. If I replace all the batteries every year, I would be throwing away about $100. I prefer to go green and save myself a few bucks at the same time by waiting until the batteries are low.

For me, safety is not an issue since all the units have low battery indicators, and I can change the batteries when needed. For people who are not handy or unable to change the batteries on their own, it would be a good idea, for peace of mind, to have the batteries replaced more often.
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LATINWHIM

[Rich P]

Dave,

Wow, that sounds expensive either way! Our local building dept only requires that the entire building be equipped (for any sort of remodel) but no requirement for hard wire or special batteries. The local electricians and smoke detector lobbies must be very strong in your area.

Sounds like most of the folks at this forum don't blindly follow the "once a year replacement" guideline. We'll see what other responses show up.

Rich

[charliex]

Ours are hard wire with battery back up. I test about twice a year. I am an adherent of the when it chirps I replace philosophy. There are Ultralife batteries with a 10 year life made just for this type of application. They are a bit more expensive but should be well worth the difference if they even last 8 years.
Here's a link
http://www.amazon.com/Smoke-Alarm-Vo...sr=8-1-catcorr

Chas

[Rich P]

Chas

Thanks for the link. What was even better were the remarks by the first reviewer:

"This battery lasts a long time which is very good if you need a battery that lasts a long time. It is not made with the usual nickel-cadmium. It is made with lithium which is much better. Lithium is a versatile element. My uncle used to take it for manic-depression and it seemed to make him better. He's dead now."

For real. Even funnier is that "1 of 1 people found the review helpful".

Too funny!

[pelligrini]

Most of Lee's reviews are pretty funny
http://www.amazon.com/gp/cdp/member-...stRecentReview

[Uncle Cracker]

I have five, all hard-wired. Nonetheless, I replace all the batteries on New Year's Day every year. Better safe than sorry, but also because they "chirp" in unison when even one battery is down, and it always happens at the most inconvenient time, is very annoying, and a couple of them are 16' in the air...

[LCHIEN]

a couple of electrical engineer's comments

Alkaline Duracels or Eveready cost about 4.50 apiece - not cheap.
10-year cells mean they last 10 years on the shelf. Not ten years under load, altho admittedly the load is small with a smoke alarm.

Again shelf life is whatever they say it is, a battery does not go along and suddenly go dead, it starts with some initial charge and the charge reduces over time. A shelf life might be defined as when it has half its original charge left. or 1/4 I don't know what criteria they use.

So a ten year battery may not run the unit for ten years - iit may only run it for 3 years - depends on the unit power/current draw.

So as expensive as the batteries are I usually wait for them to chirp.
I recently was looking at the smoke alarm end cap at lowes and looked at the 10-year units that have a 10-year battery (and that battery will run the unit for ten years not just have ten year shelf life.) I was thinking that it might be cheaper than new batteries. and then i read that supposedly smoke detectors only have a ten year design life - you should replace them so it became a no brainer. Mine were 17 years old.

[RAFlorida]

We have four detectors and I replace the

batteries whenever one starts beeping. Use to change at the start of DLS or back to ST, but after checking the batteries, I found they all had full charges left. Used those so-called no good batteries in some of my test meters and what nots. Lasted long time.
Off the thread; Lee does write some really good posts. I think there's five pages and some are good.

[sweensdv]

Dave,

Wow, that sounds expensive either way! Our local building dept only requires that the entire building be equipped (for any sort of remodel) but no requirement for hard wire or special batteries. The local electricians and smoke detector lobbies must be very strong in your area.

Sounds like most of the folks at this forum don't blindly follow the "once a year replacement" guideline. We'll see what other responses show up.

Rich

Rich,

It's not the electricians or smoke detector lobbies. This city is just so full of do gooders and ultra liberal politicians who think govt. must have their hands in everything.

Not only is the requirement for the type of smoke detectors required on the expensive side, so is the number required for each dwelling. You must have a smoke detector in each bedroom, one outside of each bedroom that is with 10' of the bedroom door, and at least one for each level of the dwelling even if there are no bedroom on that floor. I'm all for safety but I think that these requirements go a little overboard.

[JimD]

Duracells literally have exploded in my smoke detectors. I usually put in Everreadys. I have had new batteries of other brands fail quickly too. So I replace when they chirp. My smoke detectors are hard wired. So the battery is only backup. I have replaced several of the original smoke detectors. My house is 11 years old.

Jim

[Shep]

Rich,

It's not the electricians or smoke detector lobbies. This city is just so full of do gooders and ultra liberal politicians who think govt. must have their hands in everything.

Not only is the requirement for the type of smoke detectors required on the expensive side, so is the number required for each dwelling. You must have a smoke detector in each bedroom, one outside of each bedroom that is with 10' of the bedroom door, and at least one for each level of the dwelling even if there are no bedroom on that floor. I'm all for safety but I think that these requirements go a little overboard.

I bet that sounds wonderful when something burns on the stove

[Rich P]

UC

Wow, a chorus of chirping smoke detectors! I can see why you just replace them all automatically. How would you ever find the low battery one that set them all off?

I wouldn't do mine on New Years Day...usually too fuzzy.

RP