CO Sensor Issue : User Self Inflicted

A SS customer since April of 2012, I take pride of my knowledge with SimpliSafe products and services, possibly a bit too much.  A CO sensor, one of 3 in our house, started chirping this afternoon. Got my step ladder, took it down from the ceiling mount, changed the batteries and put it back up. Still beeping, I scratched my head and finally called support.  Confirmed the serial number with the agent but then I started to remember how old it was....and promptly thanked him for his assistance and went to my computer to the search support tool. Ooops.  Whereas smoke sensors have a life of 10 years, CO sensors are 5, and using my superior knowledge :-) of math did the mental calculation of 2025-2018 equals....yeah, you get the idea.  Time flies when you are having fun....