Suunto 7 Altitude Issues

[Chris Van Sickle]

Here’s what I’ve found works, most of the time:

I’ve had 4 Sunnto 7’s as follows:
Bought 1st in winter 2020 -> had to send for RMA/repair that first summer due to dead after swimming w it. Had altitude issues as described by many here.

Replacement watch was fine for awhile, then eventually had altitude issues. Then IT bricked, and had to replace IT under warranty a 2nd time, the 2nd summer.

Bought a 2ndary Suunto 7 so I wasnt without my watch/recording all summer for the 2nd summer in a row. Altitude was fine - but the replacement RMA came back too soon for it to start acting up.

Now 6 months later, the altitude on the 4th watch (2nd RMA) is acting up for the 2nd time. A known 170m ascent loop read 390m yesterday…

The 1st time a few months ago I cleaned it with the baby toothbrush. This time, I tried doing that 3-4 times and it didnt improve things.

My test: watch is on window sill, good GPS, WILDLY jumping up and down in altitude while recording.

***Decided its probably a varying combo of moisture and/or dirt that can affect the baro hole. ***

With that in mind, I put it in the fridge overnight, powered off, after thoroughly and gently cleaning the baro hole with baby toothbrush under running warm water.

Now, watch has been on window sill for 30 mins with 0 ascent, 0 descent - which is night and day from yesterday’s tests which had ~100m up and down within 2 mins.

RECOMMEND: clean baro hold gently with baby toothbrush whenever it starts acting up. If that doesnt fix your alti readings, leave overnight in fridge to wick moisture out.