Does this work witha 2 wire system or does it require the 3rd wire for power? Really having trouble finding one that works with a 2 wire system like the old nest did and I stalling a C wire is not an option null

Question

GeorgeT · Accepted Answer

Invest in a multi-volt tester. More or less $15. Test your wires and find one that has 24 millivolts or 120 and 240. Now you know which wire is your common wire. You should be okay from here.

Nest Support · Answer

Nest thermostats are designed to use very little power, and in many cases they can use your system’s heating and cooling wires to get enough consistent power. And though Nest thermostats would generally work without a common (C) wire, there are some systems that would require a C wire on the new Nest Thermostat like a heat only or cool only systems. But sometimes, you may need to connect a common wire (C wire) or power accessory, like the Nest Power Connector, to make your system compatible. Visit the online compatibility checker for more details here: https://support.google.com/googlenest/answer/9246656

Answered by Nest Support 3 years ago

“Does this work witha 2 wire system or does it require the 3rd wire for power? Really having trouble finding one that works with a 2 wire system like the old nest did and I stalling a C wire is not an option”

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