Smoke alarms

[zig <wallstreet123456@xxxxxxxxx>]

I have three two wire smoke alarms hard wired to my Napco 3200 panel.
The smoke detectors are over 13 years old and they labeled ESL
(Photoelectic)  2-Wire Smoke Detector.
Should smoke detectors be replaced after a certain period of time and
if so what Brand/model do you recommend to replace these with and what
are the
steps required to install the new ones?

As always thanks for your help.


Steven