Your property may be fitted with smoke detectors, if this is a private house, ie not a flat in a block once the tenancy is signed you are responsible to keep this maintained and working. We recommend you test these monthly.
They will normally be mains powered with a battery back up, if the battery is low the detector will let out an intermittent chirp sound to inform you to replace the batteries. Please see the below video on how to replace the battery and test the most common type of unit.
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