On 10/01/2014 7:47 AM, trader_4 wrote:
....

... since these are both AC and battery powered, why does the battery
go out in a year, just as fast or faster than battery only powered ones?
....

'Cuz they're a poorly designed (read "cheap to build") and don't
actually cut the battery (completely) out when A/C is on nor use
rechargeable batteries would be the likely cause...

I've not looked, but I'd think such a unit would be readily available
altho undoubtedly at a somewhat higher price point. There are just the
minimal one each floor of the old battery-powered type here as nothing's
been modified since all the recent Code changes. So, that's just three
and the once't a year deal isn't so bad as there are no cathedral
ceilings, etc., ...

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