ecobee smart thermostat: what its lights, symbols and messages mean

An ecobee shows what it is doing with the colour of one icon: the flame for heat, the snowflake for cool, half of each for Auto. Orange or blue means it is asking the system to run; white means it is not. It has no internal power source, so a thermostat that keeps restarting or says “Calibrating” has lost power from the heating and cooling system.

The mode icon sits at the top middle of the main screen. Depending on the model, a call for heat or cool shows as a coloured icon or as a coloured line around the edge of the screen. Alerts and reminders appear on the screen, in the app and by email.

1. “Calibrating”, or the thermostat keeps rebooting

   The thermostat lost power and restarted. ecobee says it has no internal power source: it is powered by your heating and cooling equipment, and if that has no power the ecobee will not power on.

   ecobee smart thermostats. 4 steps from ecobee on its page. About wiring or power: only ecobee’s own instruction is repeated.

2. Flame icon orange, or an orange line around the edge

   The thermostat is asking the heating to run.

   ecobee smart thermostats (icon or edge line depends on the model). ecobee gives no step for this.

3. Flame icon white (not heating)

   The thermostat is not currently trying to run the heating. If the room is below the set temperature, ecobee says a setting is usually why: the room must fall below the set point by the heat differential (0.6 to 1 °F or 0.3 to 0.5 °C by default), and a heat pump without auxiliary heat will not run below the compressor minimum outdoor temperature.

   ecobee smart thermostats. 1 step from ecobee on its page.

4. Flame icon with an exclamation mark

   Auxiliary heat has been temporarily disabled to save on energy costs. The compressor-to-aux runtime or temperature thresholds were reached, but the outside temperature is above the Aux Heat Max Outdoor Temperature setting.

   ecobee thermostats controlling a heat pump with auxiliary heat. 2 steps from ecobee on its page.

5. Snowflake icon blue, or a blue ring around the edge

   The thermostat is actively calling for a cooling cycle to run.

   ecobee smart thermostats (icon or ring depends on the model). ecobee gives no step for this.

6. Snowflake icon white (not cooling)

   The thermostat is not currently trying to run the cooling. If the room is above the set temperature, ecobee lists the usual reasons: the cool differential has not been reached (0.6 to 1 °F or 0.3 to 0.5 °C by default), a cooling cycle ended less than 5 minutes ago, a utility Time of Use program is letting the temperature rise, or it is below the compressor minimum outdoor temperature.

   ecobee smart thermostats. 1 step from ecobee on its page.

7. Half flame, half snowflake icon

   The thermostat is in Auto mode (the flame alone is Heat mode, the snowflake alone is Cool mode).

   ecobee smart thermostats. ecobee gives no step for this.

8. Furnace Filter reminder

   It is time to clean or replace your furnace filter.

   ecobee smart thermostats. 1 step from ecobee on its page.

9. Low Temp Alert

   The temperature in the home has fallen below the level you set. ecobee sends it to help prevent damage to your home from freezing.

   ecobee smart thermostats. ecobee gives no step for this.

10. High Temp Alert

    The temperature in the home has risen above the level you set. ecobee sends it to help prevent damage to your home from excessive heat.

    ecobee smart thermostats. ecobee gives no step for this.

11. Aux Heat Runtime Alert

    The auxiliary heat source has run for more than the set amount of time in 24 hours (3 hours by default).

    ecobee thermostats controlling auxiliary heat. ecobee gives no step for this.

Find a light, symbol or code on any maker’s thermostat →