Suunto 7 Altitude Issues

Stephan Zak

Hello everyone,
I also had the problem that too many altitude metres were always displayed.
instead of 21 metres, it was 1123 m, for a hike of 7.53 km.

I also sent the watch to support once. they said everything was fine and send it back.

After cleaning the baro sensor with a small brush, everything works as expected again. I will run/bike a few more laps but it already looks good.

i didn’t think at first that the secret was actually a small brush

Aleksander H

I’m starting to think we need a sticky topic called “First steps to fixing altitude issues”

freeheeler

@egika said in Suunto 7 Altitude Issues:

Fused alti is supposed to correct the sensor with GPS signal

that was my expectation, but it didn’t.
It happened only once, at least that I am aware of…

Kurt68

@stephan-zak I cleaned the sensor again. I won’t be able to do an exact test until tomorrow, but I was able to do a short lap straight away. The altitude measurement now seems to be working again. You have to clean it very thoroughly. I was always careful not to damage the sensor, but apparently you shouldn’t be careful ‍️

Kurt68

extensive test run done today. S9 517m S7 523m ascent. Everything OK. Suunto Support should receive training there

Mff73

@kurt68
Sensor Cleaning Powoa

Aleksander H

@mff73 Maybe they should start bundling toothbrushes with the S7

freeheeler

@aleksander-h
first thing Suunto 7 owners do in the morning after brushing their teeth: brushing the baro sensor

Aleksander H

@freeheeler said in Suunto 7 Altitude Issues:

first thing Suunto 7 owners do in the morning after brushing their teeth: brushing the baro sensor

Preferably not the same toothbrush

aeroild

@aeroild said in Suunto 7 Altitude Issues:

The altimeter was fine the first six months then getting gradually worse to the point where it would record an ascent when I was in fact moving downhill. It went from recording a detailed altitude profile with small ups and downs to a all smoothened out profile with a max altitude that could be a doubling of the real altitude. Service in Finland did a lab test to check the sensor and said there was no problem with the sensor so I did more tests/runs/walks to confirm the issue and sent it back to Suunto, this time HSH Sport in CZ. I’m looking forward to their conclusion.

I want to give HSH and Suunto some praise. Two weeks after doing some test of my watch suggested by Suunto and then sending the watch to HSH, I got a new watch back! Without altitude issues! Now my watch records the altitude almost spot on the altitude according to the map data. Thank you Suunto!

freeheeler

interesting alti graph behaviour on my wife’s S7…
she obviously did some nice 350m/min… Mr. Jornet would be jealous I guess

green is alright, yellow is what it should be (similar to the beginning before the ascent) and red is clearly cheating by the watch

Chris Van Sickle

I came here to complain about the same issue. My cycling and hiking recordings are wildly inaccurate in terms of altitude. If I get Strava to correct it, I usually drop between 50 and 75% of the ascent my S7 records. If I create a route on the Suunto app, the altitudes pre-excercise are fairly accurate. I believe it’s because of the mild flucts off track due to GPS insensitivity - it then records tons of extra 1-2 meter changes every few meters across the ground where there aren’t any on the actual route. This happens on Best GPS setting, and on Good, clear skies or in the forest. The ascent metric is essentially useless and I have to have Strava fix every recording.

freeheeler

@chris-van-sickle said in Suunto 7 Altitude Issues:

I believe it’s because of the mild flucts off track due to GPS insensitivity - it then records tons of extra 1-2 meter changes every few meters across the ground where there aren’t any on the actual route.

I don’t think so, since S7 has a barometric sensor. It must be something else.
We (my wife and I) did not find out yet what causes it with her watch as it is very rarely happening.

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