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I have a condo and it has the original smoke detectors, FireX.
Probably about 20 years old. they don't take batteries, that's
probably why they have not received much attention. The are hardwired
to AC with a signal wire to the other 2 detectors. Don't believe they
are on a separate circuit, should they be ?

Should they be replaced ?

Recommendations !?

Usually, the max recommended life is 10 years. Here's a link that says that
in the middle of Page 2 of the document.


http://www.firexsafety.com/NR/rdonly...523English.pdf



If you are in a condo, you may want to check with the condo association to
find out if your smoke alarms are interconnected with alarms in other units
in the building or an outside alarm if they go off.

You may be able to switch them with detectors that also have a battery
backup -- not sure.