RT520 Series Boiler Plus Compliant Thermostat | 5.1. Low Battery Warning & Changing Batteries | Help Center
5.1. Low Battery Warning & Changing Batteries
RT520RF - Changing the Batteries
RT520RF : Changing the Batteries (5.1.1) . Description : The batteries are located in a compartment behind a removable cover on the back of the thermostat. If you have a low battery warning ...