David Nebenzahl wrote:
On 1/18/2011 4:53 AM John Grabowski spake thus:

OK, I am in disagreement with a friend and would like your feedback.

At 3:00 this morning, a battery was dying in my smoke alarm and
started chirping. It makes my little dog shake like crazy. So, I had
to go to the garage, get the tall ladder, and remove the battery.

My friend said to just flip the switch at the fuse box and that will
take care of the chirping noise until I get up to put in a new
battery.

If the battery is there to backup the smoke alarm during a power
outage, why would shutting off the switch in the fuse box keep the
battery from chirping?

*Shutting off the power can make the smoke alarm chirp because of
that. I've replaced a few smoke alarms for customers that even when
the battery is removed they continue to chirp because they store a
small amount of electricity. Pressing the test button drains any
remaining power.

Sounds like two levels of backup power: battery, and a supercap for
if/when the battery fails. (Or maybe just a good-size electrolytic cap?)


H,
First of all if the alarm unit is more than 7 years old, replacing it is
better idea. I just did that, all our units are replaced with dual
sensing ones(smoke, flame=temp.) and they are all hard wired in daisy
chain with back up batteries. If it is chirping better find out why ASAP.