Edge 840 temperature is inaccurate

I recently upgraded from Edge 520 to 840. I've noticed that at the colder temperatures the 840 temperature value is approximately 3 degrees Celsius too high at temperatures around 10 degrees Celsius and under. Example: at 3 degrees actual (measured with a Fluke with thermocouple and my edge 520) the Edge 840 shows 6 degrees. The 520 and 840 were outside in airflow for more than 20 minutes to equalize the internal temperature to ambient. Is this temperature inaccuracy expected? I don't think it is good enough. I rely on the unit to tell me the temperature, especially around zero Celsius where ice on the paths could be possible. It is quite a disappointment to upgrade from the 520 and get temperature readings so far off reality. Hello Garmin - are you aware of this? I would be interested if this is a fault with my unit or not.

  • Yeah. Garmin Edge units' temperature is the internal temperature of the barometric sensor, which needs to know its own temperature to accurately measure pressure.  It only coarsely reflects ambient temperature.  Best is to use the separate Garmin Tempe sensor which is designed to more accurately measure ambient temperature.

  • Thanks for the reply. Quite disappointing that my 520 was very accurate for temperature, yet the newer 840 is not. The 840 seems to get inaccurate below about 10 degrees. It would be very simple for Garmin to write an offset into their firmware to correct the output to the user facing temperature value rather than just copy the internal sensor raw value. I guess the internal sensor temperature is affected by the battery temperature or something else internally creating heat.  I don't think it is ok to expect the user to buy another sensor to correct what Garmin could correct with software, especially considering the price of the 840.