A Google Nest Thermostat (2020) that shows the wrong time, or whose schedule fires at the wrong hour, is almost always using the wrong time zone, and the fix is in the Google Home app, not on the thermostat. The thermostat takes its time and time zone from the Home's address and from the internet, so open Google Home, tap Home settings, then Home address, and check it. If you moved, traveled or changed the address, update it, and the thermostat corrects itself when it next connects.
The checks in more detail
If the thermostat is offline, its clock can drift or freeze, so check that it is connected to Wi-Fi. A schedule that runs an hour early after a clock change may reflect daylight saving: the thermostat adjusts when the time zone rules apply, but an outdated home address or a failed internet time sync can delay that. Restarting the thermostat from the Reset menu forces a new time sync. Check the schedule itself in the app: a schedule set in one time zone and a Home address in another shows the schedule at odd hours.
Eco temperatures and Home and Away assist also use the time and location, so a wrong time can make the thermostat think you are away. If the display shows the correct time but the app shows another, refresh the app or reopen it. A thermostat that loses power frequently, because of a weak C-wire, restarts and may show the wrong time until it reconnects. After a power cut, wait a few minutes for the clock to resync. If the problem persists after correcting the address, send feedback from the app, and check the thermostat's firmware version in Settings, since Google fixes time bugs in updates.
Remember that a wrong time can make your heating run at the wrong hours and cost money, so check the schedule soon after any change. Because schedules depend on time, a thermostat with a wrong time can heat an empty house or leave a cold one, so check the time display against your phone each season. Daylight saving changes can leave a one-hour offset until the thermostat updates, and a restart helps. If the display time is right but the app shows the wrong time, close and reopen the app, which refreshes the data from the thermostat.
Differential
Likely causes of “Nest Thermostat shows the wrong time, state or sensor reading”, and how to tell them apart
- 1
A wrong Home address or time zone
What separates it The time is for another place
How to confirm Correct the Home address in Home settings
- 2
An offline thermostat
What separates it The clock drifts
How to confirm Reconnect it to Wi-Fi
- 3
A daylight saving mismatch
What separates it The schedule is an hour out
How to confirm Check the address and restart the thermostat
- 4
Frequent power resets
What separates it The time resets after power loss
How to confirm Fix the power wiring
- 5
A schedule set in another zone
What separates it Events fire at odd hours
How to confirm Review the schedule
Before you touch a setting
Record this first — changing settings destroys the evidence
- The time on the display and in the app
- The Home address saved
- Whether the thermostat is online
- Whether power cuts happen
Try in this order
0 of 6 completedCheck the Home address
ReversibleGoogle Home, Home settings.
Correct it if you moved
ReversibleEnter the new address.
Check the thermostat is online
ReversibleIn the app.
Restart the thermostat
ReversibleFrom Settings, Reset, Restart.
Review the schedule
ReversibleFor odd hours.
Send feedback if it persists
ReversibleFrom the app.
Model-specific
What is true of this model and not of its siblings
- Address controls time
- Google Home sets the zone.
- Offline drift
- A disconnected thermostat can lose time.
Stop boundary
When this stops being a self-service repair
- !If the time stays wrong after the address is corrected, contact Google Nest support
- !If it resets often, call an HVAC technician
- !Check the firmware
Evidence ledger
Sources behind this answer
Google's restart and factory reset steps for Nest thermostats.
Power, Wi-Fi and wiring checks for a Nest thermostat.
Setup connection checks for Google and Nest devices.
Exact questions
Common questions
Why does my Nest Thermostat show the wrong time?+
The Home address or time zone.
Does it keep time offline?+
It may drift.
Why did my schedule shift an hour?+
Daylight saving or the time zone.
Will a restart fix it?+
It forces a time sync.