RBoy
(www.rboyapps.com - Making SmartThings Easy!)
2
That’s an excellent thermostat even today and is super feature rich. There are also some excellent Honeywell zwave thermostats like the T6 and T5 which are battery operated.
See this first post for a list of zwave thermostats compatible with SmartThings and have battery options
The CT-xxx do not support OTA updates. They are still working here (we have 6 of them setup in our labs). You may need to exclude and re pair them or press the black reset button which helps if the connection stability is lost.