Saturday, October 27, 2012

Replacing batteries in hard-wired smoke detectors

Now, don't any of y'all laugh at this next part.  Centerpointe Section 9 has an overabundance of first-time home buyers because its construction coincided with those very special federal tax credits intended to help alleviate some of the economic impacts of the Great Recession

(Incidentally, it amazes me that stories have not been written about how this tax break inspired one of the largest mass waves of "living in sin" cohabitation in American history, as innumerable young couples delayed marriage and instead used their carefully-saved wedding money as downpayments on their houses, but let me not digress.)

So a lot of first-time couples rushed not into marriage but into home-buying with perhaps less planning and due diligence than they might have under more normal circumstances. 

You can occasionally see one of the downstream residual effects of this when you walk into one of Section 9's now-2.5-year-old houses and hear a smoke detector chirping in some distant room.  Don't laugh, but not everybody knows how to deal with these things.  It's not been more than about a month now since I helped one such family to isolate the cause of their incessant chirps and remedy it.  2.5 years post-construction is just about the right amont of time needed for all those batteries to start going bad.  The neighborhood-wide chirp-a-thon is now beginning!! 

On November 4, Daylight Savings time will end and at that time, we'll all be bombarded with PSAs about replacing the batteries in our smoke detectors

The trouble with that is, owners of newer houses that have hard-wired smoke detectors (as opposed to the free-standing battery-operated kind) tend not to do it.  If, in their youthful innocence, they even realize that their detectors contain batteries at all, they'll snap to the realization that the batteries are simply there as back-up in case of power failures.  Given that power failures almost never occur, this battery-replacement task can lose a sense of urgency.

But all you will need to inspire you to take it seriously is one detector to start chirping like an auditory version of Chinese water torture at 3:00 a.m. and you'll never make that particular deferred maintenance mistake again.  They never start chirping at a convenient time like 6 p.m.  They always seem to wait until the dead of the night and then you're forced to stumble like a zombie into your garage to fetch a ladder in order to deal with it.  Not fun. 

They start chirping because, even though they run on household electricity, the newer models are designed to warn you with chirping when their back-up batteries run low.  So rather than having to get awakened in the middle of the night, here's what I suggest instead: replace the nasty little things now and enjoy your well-earned future period of uninterrupted sleep.  Here are some suggested common steps to accomplish the replacements, although you need to consult with your manufacturer's user manual for your particular smoke detector to be fully sure you're doing this correctly.  My short-hand tips are not a substitute for any manufacturer's instructions.  Your builder would have left that manual in your house along with every other appliance manual.  If you don't have one, look at the brand name of your units and contact the manufacturer. 
Every home built in the past few years is likely to have somewhere between six and twelve smoke detectors in it, and they're probably all hard-wired together.  Our house has seven: one in each bedroom and one in each hallway, no matter how short the hallway.  Building codes dictate the locations of these things and I'm not sure of the exact requirements, but generally those are the areas where you'll find them. 

So you're going to need to buy a big package of 9-volt batteries in most cases.  Here's a tip: take a Sharpie and write the date on each battery for future reference.  I use the YYYYMMDD format because that's the only truly date-sortable numerical representation for dates.  (A lot of scientific, computer programming, and technical workers are trained to use this format).

I don't recommend one battery brand over another.  Sam's Club sells this brand above in an 8-pack, which was convenient for us.
This is similar to what you're going to see in a modern smoke detector: the unit un-screws from the ceiling mount (you can gently hand-turn it like the lid of a jar until it releases - note the wires extending up into the ceiling - don't pull those loose from either the unit or the ceiling) and there's a little trap door that you can lift to see the battery underneath.  There's usually a plastic pull-tab to help you release the existing battery (such as this yellow one). 

IMPORTANT:  Make sure you note the orientation of the existing battery with respect to positive and negative battery poles (those nubs on top of the battery) so that you don't put the new battery in upside down.  If you make that mistake, there might not be an immediate way to tell, except that the smoke detector will start chirping all over again and you might not know if it's because your replacment battery is actually dead, or because the battery is simply upside-down in the unit. 
In many newer models, there's another little safety item which is apparently designed to prevent you from re-mounting the detector on the ceiling without first putting a new battery in it.  This red lever pops up and will prevent you from re-closing the trap door unless a battery is holding the lever down.  So in this example, the new battery has to go on top of both the yellow pull tab and on top of the red lever before the trap door can be properly closed.
In a perfect world, everyone would replace ALL of their smoke detector batteries in one fell swoop. 

In the real world, what often happens instead is that one of the danged things starts chirping, and the squeaky wheel gets the grease.  People often don't have a half-dozen or a dozen batteries on hand at once, so they might replace just one battery at a time... and then forget which detectors have newer batteries than others. 

Either that, or people may simply overlook one or two smoke detectors (there's more of them in the average house than most people realize) and then a few weeks after they thought that they have completed this replacement job, something again starts up with those exasperating dead-of-night chirps.

For this reason, I take a small piece of masking tape and write the date of battery exchange on it, and stick that on the outside of the unit, being careful not to cover up any of the little buttons or openings on the plastic case.  That way, if something starts making noise, I can start trouble-shooting by first going around the entire house and doing a visual inventory of the units from the ground without having to get a ladder and pull them one-by-one off the ceiling again. 

Someone will probably patent this very obvious and very useful date-incorporation idea and make a million bucks off it, but that someone will not be me. 
Remember, these statements above are just some tips that may or may not be appropriate for your brand and model of smoke detector - these comments and opinions are not intended to be a substitute for your manufacturer's operating instructions. 
These are the batteries that came out of the seven smoke detectors that Meritage installed in our house.  Note how their advisory wording discourages trash disposal because, although they are mercury-free, they do contain lead.  If possible, dispose of them at a household hazardous waste event like the one behing held today at Gulf Greyhound Park
Happy chirp-hunting.


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