When I replaced the mains interlinked with new I think the old ones would fit but the old were yellowed and covered in paint from decorators/owners so I used the new ones. Much smarter. Check the age of the wireless ones. They may be due replacement anyway. All mine were well over 10 years old!
Current guidelines on smoke alarm placement may be relevant (and even compulsory in some Countries of our United Kingdoms). So you may want to add more rather than go back to the wired ones only. (You can get some that combine wired and wireless with addon modules, including Aico/EI that your base unit is from).
Current guidelines on smoke alarm placement may be relevant (and even compulsory in some Countries of our United Kingdoms). So you may want to add more rather than go back to the wired ones only. (You can get some that combine wired and wireless with addon modules, including Aico/EI that your base unit is from).