nis999

I have inherited a 3-storey building, split in the 1950's into 2 flats, 1 ground floor and the other on 1st & 2nd floors. At some time in the past the top flat was let with multiple occupancy, but for the previous 10 years just let to 2 separate families. Each flat has its own front door and there are no common areas. The old fire alarm system had been left in place, switched on, but not checked for several years and the previous owner had fitted independent smoke alarms. The old alarm system has recently stated giving false alarms. Am I required to maintain/replace this system, or can it be removed/switched off? Any advice gratefully received!