On the covered Google Nest thermostat, N262, N263, N412, N413 means in extremely cold weather only: no power to the Y1 wire is detected, the same cold-weather shutoff as the E10 group. N412 also appears on Google's list for a system that needs maintenance. First, check the thermostat battery level and replace the batteries if needed.
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0 of 4 completedWhat to do first
ReversibleCheck the thermostat battery level and replace the batteries if needed.
Correct only the documented fault domain
ReversibleGoogle's steps for these codes: check the battery level and replace it if necessary, then install a common wire or a power accessory such as the Nest Power Connector to prevent a repeat. Because the same air conditioner safety switch can be the cause, and a system that needs maintenance can produce N412, contact an HVAC professional if it returns.
Understand the cold-weather cutout
ReversibleThese codes mean no power reaches the Y1 wire in extremely cold weather. Air conditioners have safety devices, low-pressure or cutout switches, that stop them in extreme cold to protect the system.
Fix the power and check the batteries
ReversibleGoogle's advice for this family of codes includes checking and replacing the thermostat's batteries and, to prevent it, installing a common wire or a Nest Power Connector.
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Common questions about “Google Nest thermostat code N262, N263, N412, N413”
What does N262, N263, N412, N413 mean on a Google Nest thermostat?+
In extremely cold weather only: no power to the Y1 wire is detected, the same cold-weather shutoff as the E10 group. N412 also appears on Google's list for a system that needs maintenance.
Do I need to do anything about N262 in winter?+
If cooling is not needed, it is informational. If the thermostat is also losing power, add a common wire or a Nest Power Connector.