I have the old, original single faucet and the newer 4…both running with the same batteries since May. On the new controller I keep getting emails that my batteries are low…but they are not, its some bug they won’t fix. Once in awhile I can unplug/replug the controller and things are good for another month. In the old unit I am using the same batteries I took out when I winterized last fall, so second season. I am using energizer lithium batteries. I even have the controllers working with my home automation so they get “polled” frequently for status updates even when not in use.