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Install a smart thermostat
Trigger
Upgrade
Who does it
DIY
Est. time
1-2 hrs
Est. cost
$130-280
Difficulty
●●○○○
Step by step
Turn off power to the HVAC system at the breaker.
Label existing thermostat wires with a photo before disconnecting.
Mount the new base plate and connect wires to matching terminals.
Use a C-wire adapter if your system lacks a common wire.
Restore power and complete setup through the manufacturer's app.
Video guide
How to Install a Smart Thermostat - This Old House
Watch this guide
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