Nest thermostat wire connections

Old 12-15-21, 12:25 PM
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Nest thermostat wire connections

Before I install my new Nest Learning Thermostat, I thought I'd check in with you all in case you've done it before yourself. It's an assumptions check more than anything. The first pic below (square plate with two rows of connectors) is the connector plate for my new HVAC system. The second pic below (round plate) is the Nest plate with which I'd like to replace the old one.
Three of the five wired connections seem pretty straightforward: the G, C, and R wires go right to their counterparts on the Nest plate. But the Yellow wire connecting into the legacy plate could go to the Y1 or Y2 connection on the Nest plate, and likewise there are W1 and W2 options on the Nest plate not included on the legacy plate. Should I just default to connecting the yellow wire to Y1 and the white wire to W1, or is it more complicated than that?

Old 12-15-21, 12:37 PM
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An easy wiring change......

Y --------> yellow ----> Y1
G -------> green -----> G
C -------> blue -------> C
W ------> white ------> W1
R ------> red ---------> Rh

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