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Altimeter/Elevation Readings

Former Member
Former Member over 7 years ago
Is anyone able to explain how the VA3 altimeter/elevation readings are calculated? I live at 466' above sea level. I am former military and this elevation has been confirmed with a military GPS as well as several online sites and my cell phone. When I complete an activity at home, Garmin Connect shows my elevation to be + or - 10' of the 466' when using my FR235 for the past 2 years. My VA3 is a different story. It records my elevation anywhere from 420-490' since my purchase back in mid September. That's issue number 1. Issue number 2. As a test I downloaded several widgets, applications and data fields that record elevation. Every single one of those shows my elevation at 331' + or - 2'. I have my VA3 set to auto calibrate the altimeter. Yes, I can go in and manual adjust the calibration, but that doesn't explain or solve my issue. Is anyone else having this happen to them?


Update: I manually calibrated my VA3 to the correct elevation. I don't expect the VA3 to be spot on with accuracy, but to be off by 25-30% on elevation isn't very good. I'm one of those guys that wonders if the VA3 is that far off on elevation, what about it's calculations about steps, calories burned, speed, etc... I hoping there's an explanation about the elevation readings I'm not aware of that will make me feel better about the VA3's functions, because I'm starting to question them.
  • 0 over 7 years ago
    One thing different is the 235 doesn't have a baro altimeter, and when an activity is uploaded to Garmin connect, by default, "elevation correction" is enabled by default. for devices with a baro (like the va3) it's disabled by default. The "elevation corren" uses some known data is some way to account for GPS inaccuracies.

    One thing you might try on the va3 is to calibrate the altimeter, but turn off auto-calibrate for it. I recall that worked for some folks with the vahr., as based on where you are, the GPS elevation can be a bit off. I've run tests where I had a watch with a baro along side a fr230, and on the same walk, the baro showed about a 40' change in elevation, but the GPS based 230 showed 400' (when the data wasn't adjusted by GC)
  • 0 over 7 years ago
    the VA3 barometer/elevation readings are completely wacky, I can see it shifting slightly every day until it puts me 10m under water and I live on a big hill. Then it would recover after a few days and it would start the journey again. This is with auto calibration on an multiple GPS tracked exercises recorded in that time (which I'd imagine should correct the reading). I am glad I don't really rely on these readings for what I use the watch for but I can imagine some users will be pretty fed up. Hopefully a future firmware update will fix it.
  • Former Member
    0 Former Member over 7 years ago
    One thing different is the 235 doesn't have a baro altimeter, and when an activity is uploaded to Garmin connect, by default, "elevation correction" is enabled by default. for devices with a baro (like the va3) it's disabled by default. The "elevation corren" uses some known data is some way to account for GPS inaccuracies.

    One thing you might try on the va3 is to calibrate the altimeter, but turn off auto-calibrate for it. I recall that worked for some folks with the vahr., as based on where you are, the GPS elevation can be a bit off. I've run tests where I had a watch with a baro along side a fr230, and on the same walk, the baro showed about a 40' change in elevation, but the GPS based 230 showed 400' (when the data wasn't adjusted by GC)


    Yes, I'm aware that the FR235 doesn't have a barometer/altimeter and if I'm not mistaken, took elevation levels based on GPS. Those were correct for me. Is the barometer on the VA3 that poor that I have a 25-30% error in readings? On your VAHR/230 test, which was correct? The 40' barometer reading or the 400" GPS?
  • 0 over 7 years ago
    But with the 235, the elevations are "corrected" when upload to Garmin Connect because it is using GPS. Try looking at some of your 235 activities and turn off the elevation correction for them in GC.
  • Former Member
    0 Former Member over 7 years ago
    I just recently sold my FR235, so I can only look at past activities. Will they still adjust previous readings by turning off the elevation correction? A couple of more questions Jim. Why would the barometer change elevation readings from the actual elevation? What benefit does a barometer give the VA3 if it's giving me an elevation reading of 331' at 466'?
  • 0 over 7 years ago
    You can look at old stuff and turn off the correction. In general, the baro will be more accurate than GPS based elevation, but over time there are pressure changes that don't relate to elevation - storm fronts, etc. (I live in a desert and this time of year we don't really get any storms)

    On my va3, I calibrated to the known elevation at my house, and I'll see that change maybe +/- 10' to 20' day to day. (I'm at 1260') I turned off auto calibration an hour or so back to see what that may change.
  • 0 over 7 years ago
    Glad to see this post, have been wondering if other people have had the same problem. Elevation is way off, I had the VA hr before up grading and I never had to calibrate anything and elevation was always in a reasonable range, and always followed the correct ascents/decent of any particular run. Today started a run from home at 80m graph started out at 80m but then from there seemed to make it up as it went along until I was under sea level and then finishing at home the graph showed 40m.
    Check out my running activity on Garmin Connect. #beatyesterday
    https://connect.garmin.com/modern/activity/2327898724?share_unique_id=3
    Check out the elevation graph.
  • 0 over 7 years ago
    The va uses GPS for elevation. It doesn't have a baro altimeter. So when you looked at an activity uploaded from the va, the elevation was "corrected", so it's actually not what the watch is seeing.
  • 0 over 7 years ago
    According to the garmin Web site, specs for VA hr and VA 3 both have a barometer. Does anyone know how to change the elevation correction in settings. Cheers.
  • 0 over 7 years ago
    Oh, I thought you said va and not the vahr.

    You can calibrate the altitude in settings: Long press, settings, sensors, altimeter, calibration. There's no way to calibrate the baro itself. You'll see the MSL adjusted value when it's displayed, which relies on the altimeter calibration (to know your altitude and adjust for MSL.)