I replaced three old Admeco 5816 Wireless Transmitters with new 5820 Slim Line Wireless Transmitters and sent my new serial numbers off to my installer to have all three added to my system.
He said it's taken care of (and charged me $40 for the "install"), but all three zones don't register the "open/closed" state. They register a tamper if I try to remove the cover, but nothing when it comes to opening the window.
Do the 5820s require different settings than the 5816? Any ideas?