Instinct Solar Abnormal Barometer Readings

Yes, pool or even bath, if the sensor is set to auto or barometer only the water will affect the sensor and the changes will be dramatic in the graph. The only way to avoid the spike in the baro graph, is to set it to altimeter only if you are swimming or in a bath. I hope this helps. 

BTW, I have reported that spike to Garmin as I have encountered it too when swimming. I tested my watch set to Altimeter whilst doing a 2k swim and the baro graph remained unchanged. 

Ajaja said:

Yes, pool or even bath

But that is not the problem here.

Former Member said:

No bathing, no shower

Former Member said:

I had no location changes because I have been at home all those time.

Ajaja said:

It’s recommended the sensor is set to auto

No, when you are at home (so your altitude stays the same) the mode should be "Barometer" if you want to capture good values for the pressure change.

bluefish said:

No bathing, no shower

There are many other situations that may influence the reading of the pressure sensor. For example:

1. Temperature changes. And that includes not only the temperature changes during the day, or when you go out, exit your bed, open the window, etc, but also when you wash your hands (possibly with hot water), the water then evaporates and cools down the sensor. Just some 4 or 5 °C difference will result in about 1 milibar pressure change (tested with my Instinct).
2. Ambient room air pressure changes due to opening or closing windows or doors, changing rooms, or because of air-condition, ventilation, etc
3. Not necessarily bathing, or heavy sweat, but a simple drop of water or sweat in the pressure sensor port can cause a mess too, especially if combined with skin or cloth pressing, or air flow blowing against the opening. 
4. Taking a lift in the building, or sometimes even climbing stairs to another floor - it may not be detected as an elevations change, and the pressure difference may be attributed to the barometric pressure.
5. Altimeter calibration - it happens automatically every night, or when you start an activity. That would not explain the short peeks, but it should be considered in other similar cases. 
6. Dirt in the sensor port may lead to a chaotic behavior too

And I certainly forgot some other factors (like for example the explosion of thermobaric bombs in the proximity, or passing of an U.F.O. overhead)

trux said:

passing of an U.F.O. overhead

Oh, you brought up a point I hadn't considered at all.

Who stays put all day. In my case I set mine to Auto mode and my Baro is always accurate to -/+ 1hPa 

Setting it to constant Barometer is not ideal as you are guaranteed to forget to change it before leaving….

Ajaja said:

Setting it to constant Barometer is not ideal as you are guaranteed to forget to change it before leaving….

No problem for me.