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Installation Overview - Complex Systems
How to configure complex systems
Heat pump systems
Configuring O/B Wire - Orientation and Activation
The majority of heat pumps use an "O" orientation, so when setting up a heat pump, this will be the default
orientation during configuration. The O or B orientation will be confirmed during Pro Setup, but it can be
adjusted at any time after installation.
You can choose whether to energize the O/B reversing valve "cyclically" during each heating or cooling cycle
or "seasonally." The "seasonally" option will keep the O/B wire energized when the thermostat is in the cooling
mode and the orientation is set to "O" and in the heating mode when the orientation is set to "B." This setting
can also be changed in the Google Home app after installation.
The Nest Learning Thermostat defaults to energizing seasonally to help reduce wear and tear on the reversing
valve, but can be configured to be energized each cycle.
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Do you have a question about the Nest Learning Thermostat 4th Gen and is the answer not in the manual?
Questions and answers
Where is the 4th generation wiring guide
The wiring guide for the Google Nest Learning Thermostat (4th Gen) can be found in its manual.
This answer is automatically generated