Aico Mains Powered interconnected battery back up Smoke Alarm X 2 Heat detector x1 3 X bases, one cable cover is missing used removed from house after a fault developed in one of the smoke detection units the heat detection unit and one of the smoke alarms appeared to be working and linked together when the alarm sounded one smoke detection unit didn't work, a fault was also corrected on the mains wiring which may have caused the problem
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