Suunto 7 Altitude Issues

Chris Van Sickle

@freeheeler you mention earlier in the thread to brush the baro sensor/hole. What kind of brush? Soft-bristled? Does it matter?

freeheeler

@chris-van-sickle
the best is a baby toothbrush… or any very soft toothbrush. but it only helps if the sensor is dirty or the hole is glogged of course

eurohiker

@aeroild i’ve had 4 brand new watches with identical altitude readings. On good gps (every 10sec) it’s 2x the altitude and best gps (every 1s) 3x the altitude. Doesn’t matter if i’m using offline, or cellular maps. Always use preloaded GPX. 4 watches have been used in over 5 countries since I travel every weekend so it can’t be the country i live in has satellite issues or something weird. I wear a t-shirt and have worn the watch tighter and looser but the baro hole clears my wrist by at least a cm in every wrist position no matter the tightness since my wrist has no meat on it. Hiked in various wind speeds of 5km/h - 40km/h gusts with no difference altitude readings (both equally all over the place). Even when I’m standing still the GPS coordinates are jumping around.

I gave up. You are one lucky guy. I would love to see your preloaded GPX file stats vs your hike stats because i’m under the impression that it’s impossible to get close to the correct altitude with a Suunto 7.
4 brand new watches with identical readings was good enough proof for me that it can’t get any better. I really don’t want to reload another watch.

Egika

@eurohiker have you tried cleaning the baro hole with a toothbrush as suggested?
My gf also had double the altitude than me in MTB and running activities we did together.
Her watch was new as well.
We cleaned it twice under running water and now her readings are perfect as well.

Just guessing here: maybe Suunto is using some type of a sealant that could clogg the hole during production??

Anyway: give cleaning a try and report back.

freeheeler

@egika
same as subaru did first with their boxer diesel

Jamie BG

@egika
I agree the S7 definitely is good at reading altitude. Matches what I can see in my F6

eurohiker

@egika I have on a couple of them but the whole toothbrush method does not work on a brand new “clean” watch. Remember these are 4 watches fresh out of the box never used.
The average consumer (99% which are not on these forums or the fb group) would never know to use a toothbrush before first use due to it not being in the instructions nor provided.

It’s most likely due to cheap GPS / Baro parts used in the Suunto 7 series or faulty algo software (pre and post April update)… I gave up on it. When any of my friends asks about my elevation on Strava, I just say divide it by 2 since I leave it on good 10sec fused alti which exactly doubles it (phone or offline maps; covered baro or uncovered; windy or not windy)

I would love to see your stats vs a pre-existing GPX file. After the 4th watch with identical doubling altitude stats, it’s hard to believe that someone has stats that is somewhat close to the GPX file loaded.

I can’t wait to get Suunto 9 Peak “snap to route” feature.

I stopped updating the forum since it was a dead end but here’s my stats in detail: https://forum.suunto.com/topic/5930/suunto-7-double-proposed-elevation-gain-6-6-trails

Brad_Olwin

@eurohiker I am sorry for your issues, as I have stated before my S7 and now both of them (one test watch and a titanium model that I purchased) record nearly identical altitude to the S9, which I know is broadly correct. My elevation gains may be different than yours as most are large, we don’t have many small hills where I live. After 4 watches this is unlikely a watch issue. I do not believe the parts are of poor quality as my experience has been quite different. Let me know if there is anything I can do to help. You might try contacting @Dimitrios-Kanellopoulos if you have not already.

Here is an image of the GPX file that I did for my run and following are the stats from QS for the S7, I deleted the SA link as this was one of three watches I was wearing. The map overestimates this one, I typically get ~3000 feet gain.

pilleus

@eurohiker said in Suunto 7 Altitude Issues:

It’s most likely due to cheap GPS / Baro parts used in the Suunto 7 series or faulty algo software (pre and post April update)…

In this case every WearOS app must record the wrong ascent. You can test it with Ghostracer to check the accuracy of the S7. I never had any problems and very precise data on several S7 watches during the last year. And I did a lot of tests with the S7 and the Spartan Ultra to compare the recorded data.

Egika

@eurohiker
I usually import tracks from GPS websites and their altitude information vary…
But I ne er get double the ascent. As mentioned my gf did, which changed after two times cleaning the baro hole.
Here two examples where my S7 recorded actually less than the pre-loaded gpx file.

eurohiker

@egika @Brad_Olwin extremely jealous.

Dimitrios has done more than enough for me. I don’t want to bother him anymore.

It is quite funny that is have an easy hike of 1000m and it says I did 2000m
https://www.strava.com/activities/5349923765.
GPX retrieved from AllTrails
When I zoom in on the trail it looks like i barely touched the trail apparently.

I’ll do a few baby tbrush brushes before my next trip this weekend and i’ll report back but it will be mainly flat where i’m going so even if the GPS bounces around it will be on the same altitude.

Another question would be why would suunto be so quick to give me a new one when they could have tried to brush it (1 of them i didn’t brush myself) and sent it back? I wonder if they just look at the info i give then don’t bother to look at it which is good service but cuts into their margins.

aeroild

@eurohiker Here’s a comparison between the altitude recorded by my Suunto 7 on a 8km run and altitude from the same route made on www.plotaroute.com On the gpx from plotatroute altitude is always overestimated. I have also made a table where I have checked the altitude data at the start, at each kilometer and at the end. Here I have also included the official data from the public map service www.lantmateriet.se. The Suunto 7 is spot on the official data!

eurohiker

@aeroild lucky, but i think it’s more of an issue when mountain hiking (which is what I mostly track for altitude) because even 1 meter away laterally can make a bit difference in altitude.

For my runs and my bikes I don’t even look at the altitude because I typically only do those activities on flat land and everything around is roughly the same altitude so when it’s bouncing around it doesn’t miscalculate as much.

isazi

@eurohiker what does this mean? This is not how the barometer works

freeheeler

@isazi
sounds like a setting I once saw in a gps: altitude from map

pilleus

@eurohiker said in Suunto 7 Altitude Issues:

because even 1 meter away laterally can make a bit difference in altitude.

???

Barometric altitude is completely independent from GPS or being on a track or not. I often use barometer only (without GPS enabled) to record the ascent/altitude.

isazi

@freeheeler yes, Garmin watches with onboard map and digital elevation model can do that do. Not the S7 as far as I know.

eurohiker

@isazi yes, but they work in conjunction

@pilleus i don’t they they are independent when they are both on. There is definitely software connecting the 2 while using “good gps 10sec alti track”. It’s pretty consistent with my dips when it bounces off trail at a different altitude.
So you are telling me I have faulty baro AND gps in 4 watches if they are independent?

isazi

@eurohiker no they don’t. The only interaction they have is that the GPS can also be used to compute elevation. If the GPS elevation error is low and the value from the altimeter and the value from GPS have diverged, the GPS elevation is used to calibrate the barometric altimeter, in some way known to Suunto.

freeheeler

@eurohiker
I’m not so sure… why would a baro watch want to rely on a saved map? you stated it already, when you hike along a steep mountain, the worst thing you can have is altitude from map, based on your track… it could be hundreds of meters wrong