Installation Guide

RTH8500
5
About your new thermostatRemove your old thermostat
1. Turn off power at heating/cooling system (or fuse/circuit-breaker panel).
2. Remove cover and thermostat, but leave wallplate with wires attached.
Is there a sealed tube containing mercury?
If so, see inside front cover of this manual
for proper disposal instructions.
Old thermostat
Cover
Leave wallplate in place