Tag: Honeywell RTH4300B Thermostat

Honeywell RTH4300B Programmable Thermostat  TURN OFF POWER at the heating/cooling system or the fuse/circuit breaker panel before you begin. MERCURY NOTICE: Do not place your old thermostat in the trash if it contains mercury in a sealed tube. Contact your local waste management authority for instructions regarding recycling and proper disposal. Need Help? For assistance…