Is it easy to change locks?
Certainly not to both questions.
You need to replace all of the batteries in all of the detectors. Be certain that one has not been put in backwards. Use a sharpie to put the date on the batteries. If the detector is not connected correctly to the power, it will also give a warning. I have a similar system and the batteries need to be replaced every 6 months. One will chirp then another, not all the same day, but very close together time wise.
1752 Lightning rod Benjamin Franklin 1775 Submarine David Bushnell 1780 Bifocal lens Benjamin Franklin 1786 Steamboat John Fitch 1793 Cotton gin Eli Whitney 1804 Screw propeller John Stevens 1830 Platform scales Thaddeus Fairbanks 1831 Reaper Cyrus Hall McCormick 1834 Electric streetcar Thomas Davenport 1835 Pistol (revolver) Samuel Colt 1839 Vulcanized rubber Charles Goodyear 1845 Pneumatic tire Robert William Thompson 1846 Rotary printing press Richard March Hoe 1846 Ether Crawford Williamson Long 1849 Safety pin Walter Hunt 1849 Water turbine James Bicheno Francis 1851 Breech-loading rifle Edward Maynard 1852 Elevator (with brake) Elisha Graves Otis 1858 Harvester Charles and William Marsh 1861 Web-fed newspaper printing press Richard March Hoe 1861 Machine gun Richard Jordan Gatling 1861 Kinematoscope Coleman Sellers
