Bill wrote:
George E. Cawthon wrote:

When one fails, does that mean you have batteries going dead, and no
warning? Scarey stuff.


later,

tom @ www.ChopURL.com



Jumping to (wrong) conclusions again. He said "when one (meaning a
battery) fails." He didn't say when the unit fails the test.


In fact the battery going out is what causes the unit to fail the test.
The unit test is primarily a battery test. As far as I know there is
no way to test the detector, except of course to build a fire under it.

Bill Gill

Now you've got me confused. I think the test is more of a
circuit test than a battery test; its already got a built in
battery check--the chirp. I've never tried to test a unit
after the unit signals a low battery with chirps, but I bet
it will still test good. If a unit fails the test without
every chirping, I think something is wrong.

Sure you can test them and some manufactures give the
instructions for that particular unit. If you have a
barbecue, you can figure out how to test the smoke unit.