One possible problem with using a battery that lasts a long time is maintenance.
When a battery needs changing annually or even twice annually, the smoke alarm is opened and somebody gets to look inside and that not only reveals whether there is an excess of dust and spider webs inside or blocking the grille, it also serves as a reminder to test the alarm periodically.
A web across the grille can stop the alarm working and when a battery lasts for five years plus, the habit of testing the alarm weekly or even monthly can soon be lost.
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One possible problem with using a battery that lasts a long time is maintenance.
When a battery needs changing annually or even twice annually, the smoke alarm is opened and somebody gets to look inside and that not only reveals whether there is an excess of dust and spider webs inside or blocking the grille, it also serves as a reminder to test the alarm periodically.
A web across the grille can stop the alarm working and when a battery lasts for five years plus, the habit of testing the alarm weekly or even monthly can soon be lost.