Ecobee Thermostat Error Codes
Complete list of Ecobee thermostat error codes with causes and how to fix them.
AUX
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Ecobee Thermostat error code AUX: Auxiliary heat active.
Technician Required
E1
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Ecobee Thermostat error code E1: Main board internal failure.
Technician Required
E2
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Ecobee Thermostat error code E2: Thermostat sensor failure.
✓ DIY Possible
E3
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Ecobee Thermostat error code E3: Remote sensor communication error.
Technician Required
E4
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Ecobee Thermostat error code E4: Furnace/AC not responding to thermostat …
Technician Required
EM
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Ecobee Thermostat error code EM: Emergency heat active.
Technician Required
SB
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Ecobee Thermostat error code SB: Standby mode.
Technician Required