On Sun, 4 Nov 2012 20:26:51 +0000, Davey wrote:

PLEASE NOTE: The Detector must have a sealed long life battery. You
cannot install a standard Detector that has replaceable batteries.

seems a bit odd.

The sensor element of a CO detector has a limited life. If you could
replace the batteries people would and long after the sensor had died...

I think some CO detectors can also detect when the sensor has died but
they can also be "poisoned" by household chemicals, whether that can be
detected I don't know.

--
Cheers
Dave.