Google Nest
Google Nest Smart Thermostats Error Codes
Complete list of fault codes and troubleshooting guides. Use the search below to find your specific error.
Advertisements
E1
Nest thermostat displays E1 and cannot control heating or cooling
No Power to R (Rc/Rh) Wire
E10
Nest thermostat shows E10 and cannot connect to Wi‑Fi
Wi‑Fi Radio or Network Configuration Error
E11
Nest thermostat displays E11 during setup or after wiring changes
Incompatible or Unsupported HVAC System Detected
E12
Nest thermostat shows E12 and may not complete setup
C Wire Detected but Power Still Unstable
E13
Nest thermostat displays E13 and may not control auxiliary heat correctly
Auxiliary Heat (W2/Aux) Wiring or Configuration Error
E15
Nest thermostat shows E15 and may shut down to prevent damage
Overvoltage Detected on Thermostat Circuit
E2
Nest thermostat shows E2 and will not operate the HVAC system
No Power to Y1 (Cooling Call) Circuit
E20
Nest thermostat displays E20 and may not complete learning or scheduling
Internal Memory or Firmware Error
E3
Nest thermostat displays E3 and cannot control the fan
No Power to G (Fan) Circuit
E4
Nest thermostat shows E4 and heating will not engage
No Power to W1 (Heat Call) Circuit
E5
Nest thermostat displays E5 and may intermittently lose power or reboot
Insufficient Power / No Common (C) Wire Detected
E6
Nest thermostat shows E6 and cannot communicate with the HVAC system correctly
Wire Mismatch or Incompatible Wiring Configuration
E7
Nest thermostat displays E7 and may not control heating or cooling correctly
O/B (Reversing Valve) Wire Error on Heat Pump System
E8
Nest thermostat shows E8 and may shut down heating or cooling to protect the system
Overcurrent or Short Circuit on Thermostat Wiring
E9
Nest thermostat displays E9 and may not complete setup or operate correctly
Internal Sensor or Hardware Failure
N1
Nest thermostat shows N1 and cannot find any Wi‑Fi networks
Wi‑Fi Radio Disabled or Hardware Failure
N2
Nest thermostat shows N2 and fails to connect to the selected Wi‑Fi network
Wi‑Fi Authentication or Configuration Failure
N3
Nest thermostat shows N3 and cannot reach the Nest service
Internet Connectivity or DNS Failure
N4
Nest thermostat shows N4 and cannot connect to the Nest service even though Wi‑Fi is connected
Nest Service Account or Cloud Connectivity Error
N5
Nest thermostat shows N5 and cannot connect to the Nest app via Bluetooth during setup
Bluetooth Pairing Failure
N6
Nest thermostat shows N6 and cannot connect to the Nest app via Bluetooth or local network
Local Device Discovery Failure
Symptom
Nest thermostat base or wall plate is loose or wobbly
Improper Mounting / Mechanical Instability
Symptom
Nest thermostat calls for cooling but AC does not turn on
Cooling Call Signal Not Reaching Condenser
Symptom
Nest thermostat calls for heat but furnace does not start
Heat Call Signal Not Reaching Furnace
Symptom
Nest thermostat display is completely blank and unresponsive
No Power to Nest Thermostat / Dead Internal Battery
Symptom
Nest thermostat does not detect Nest Temperature Sensors or shows them as offline
Bluetooth Low Energy (BLE) Connectivity Issue
Symptom
Nest thermostat does not follow the programmed schedule
Scheduling / Learning Configuration Conflict
Symptom
Nest thermostat does not turn on the fan in Fan Only mode
Fan Control Circuit Failure
Symptom
Nest thermostat fails to control a whole-home humidifier or dehumidifier
Accessory Control Wiring or Configuration Error
Symptom
Nest thermostat frequently overshoots the set temperature (too hot or too cold)
Incorrect Cycle Rate or Learning Behavior
Symptom
Nest thermostat is hot to the touch
Normal Warm Operation vs. Overheating
Symptom
Nest thermostat is very slow to respond or the ring is hard to turn
Mechanical Ring or Encoder Wear
Symptom
Nest thermostat loses Wi‑Fi connection intermittently
Unstable Wireless Connectivity
Symptom
Nest thermostat makes clicking or buzzing noises during operation
Internal Relay Operation or Electrical Noise
Symptom
Nest thermostat randomly switches to Eco mode when people are home
Occupancy Detection / Presence Sensing Issue
Symptom
Nest thermostat reboots frequently or shows a red blinking light
Low Power / Charging Failure
Symptom
Nest thermostat shows cooling is on, but air from vents is warm or not cold enough
Cooling System Misconfiguration or Low Refrigerant (HVAC-side)
Symptom
Nest thermostat shows heating is on, but air from vents is cool
Incorrect System Type or Reversing Valve Configuration
Symptom
Nest thermostat shows incorrect room temperature compared to other thermometers
Temperature Sensor Offset or Placement Issue
| Error Code | Symptom | Fault Type | Guide |
|---|---|---|---|
| E1 |
Nest thermostat displays E1 and cannot control heating or cooling
|
No Power to R (Rc/Rh) Wire | View Details |
| E10 |
Nest thermostat shows E10 and cannot connect to Wi‑Fi
|
Wi‑Fi Radio or Network Configuration Error | View Details |
| E11 |
Nest thermostat displays E11 during setup or after wiring changes
|
Incompatible or Unsupported HVAC System Detected | View Details |
| E12 |
Nest thermostat shows E12 and may not complete setup
|
C Wire Detected but Power Still Unstable | View Details |
| E13 |
Nest thermostat displays E13 and may not control auxiliary heat correctly
|
Auxiliary Heat (W2/Aux) Wiring or Configuration Error | View Details |
| E15 |
Nest thermostat shows E15 and may shut down to prevent damage
|
Overvoltage Detected on Thermostat Circuit | View Details |
| E2 |
Nest thermostat shows E2 and will not operate the HVAC system
|
No Power to Y1 (Cooling Call) Circuit | View Details |
| E20 |
Nest thermostat displays E20 and may not complete learning or scheduling
|
Internal Memory or Firmware Error | View Details |
| E3 |
Nest thermostat displays E3 and cannot control the fan
|
No Power to G (Fan) Circuit | View Details |
| E4 |
Nest thermostat shows E4 and heating will not engage
|
No Power to W1 (Heat Call) Circuit | View Details |
| E5 |
Nest thermostat displays E5 and may intermittently lose power or reboot
|
Insufficient Power / No Common (C) Wire Detected | View Details |
| E6 |
Nest thermostat shows E6 and cannot communicate with the HVAC system correctly
|
Wire Mismatch or Incompatible Wiring Configuration | View Details |
| E7 |
Nest thermostat displays E7 and may not control heating or cooling correctly
|
O/B (Reversing Valve) Wire Error on Heat Pump System | View Details |
| E8 |
Nest thermostat shows E8 and may shut down heating or cooling to protect the system
|
Overcurrent or Short Circuit on Thermostat Wiring | View Details |
| E9 |
Nest thermostat displays E9 and may not complete setup or operate correctly
|
Internal Sensor or Hardware Failure | View Details |
| N1 |
Nest thermostat shows N1 and cannot find any Wi‑Fi networks
|
Wi‑Fi Radio Disabled or Hardware Failure | View Details |
| N2 |
Nest thermostat shows N2 and fails to connect to the selected Wi‑Fi network
|
Wi‑Fi Authentication or Configuration Failure | View Details |
| N3 |
Nest thermostat shows N3 and cannot reach the Nest service
|
Internet Connectivity or DNS Failure | View Details |
| N4 |
Nest thermostat shows N4 and cannot connect to the Nest service even though Wi‑Fi is connected
|
Nest Service Account or Cloud Connectivity Error | View Details |
| N5 |
Nest thermostat shows N5 and cannot connect to the Nest app via Bluetooth during setup
|
Bluetooth Pairing Failure | View Details |
| N6 |
Nest thermostat shows N6 and cannot connect to the Nest app via Bluetooth or local network
|
Local Device Discovery Failure | View Details |
| – |
Nest thermostat base or wall plate is loose or wobbly
|
Improper Mounting / Mechanical Instability | View Details |
| – |
Nest thermostat calls for cooling but AC does not turn on
|
Cooling Call Signal Not Reaching Condenser | View Details |
| – |
Nest thermostat calls for heat but furnace does not start
|
Heat Call Signal Not Reaching Furnace | View Details |
| – |
Nest thermostat display is completely blank and unresponsive
|
No Power to Nest Thermostat / Dead Internal Battery | View Details |
| – |
Nest thermostat does not detect Nest Temperature Sensors or shows them as offline
|
Bluetooth Low Energy (BLE) Connectivity Issue | View Details |
| – |
Nest thermostat does not follow the programmed schedule
|
Scheduling / Learning Configuration Conflict | View Details |
| – |
Nest thermostat does not turn on the fan in Fan Only mode
|
Fan Control Circuit Failure | View Details |
| – |
Nest thermostat fails to control a whole-home humidifier or dehumidifier
|
Accessory Control Wiring or Configuration Error | View Details |
| – |
Nest thermostat frequently overshoots the set temperature (too hot or too cold)
|
Incorrect Cycle Rate or Learning Behavior | View Details |
| – |
Nest thermostat is hot to the touch
|
Normal Warm Operation vs. Overheating | View Details |
| – |
Nest thermostat is very slow to respond or the ring is hard to turn
|
Mechanical Ring or Encoder Wear | View Details |
| – |
Nest thermostat loses Wi‑Fi connection intermittently
|
Unstable Wireless Connectivity | View Details |
| – |
Nest thermostat makes clicking or buzzing noises during operation
|
Internal Relay Operation or Electrical Noise | View Details |
| – |
Nest thermostat randomly switches to Eco mode when people are home
|
Occupancy Detection / Presence Sensing Issue | View Details |
| – |
Nest thermostat reboots frequently or shows a red blinking light
|
Low Power / Charging Failure | View Details |
| – |
Nest thermostat shows cooling is on, but air from vents is warm or not cold enough
|
Cooling System Misconfiguration or Low Refrigerant (HVAC-side) | View Details |
| – |
Nest thermostat shows heating is on, but air from vents is cool
|
Incorrect System Type or Reversing Valve Configuration | View Details |
| – |
Nest thermostat shows incorrect room temperature compared to other thermometers
|
Temperature Sensor Offset or Placement Issue | View Details |
No matching codes found
Advertisements