Fenix 7 barometer shows an incorrect value

Along with what gaijin responded with, here is an old but still useful explanation of how it all fits together Altitude, Barometric Pressure and ABC Watches Explained | WatchUSeek Watch Forums 

and a simple but good widget for relative and absolute pressure is also available > https://apps.garmin.com/en-US/apps/00678298-6672-4228-9c82-c9aa00e43df0

As someone who actually calibrates barometers, manometers, and other precise measuring instruments, the statement that a barometer is used to display pressure at MSL is incorrect.  A barometer is a device for measuring barometric pressure at the location where it is at.  This is whether you are at sea level or not.  It can be used to infer altitude IF it has been properly set at sea level and can be influenced by weather (high and low pressures) as well.  Without knowing what seal level barometric pressure was, it is difficult to know whether or not your watch's barometric pressure is off or not.  However, if it is showing the proper altitude, then it is probably correct. Additionally, it is not that far from what it should be reading for barometric pressure at 1100 meters.  Per the chart linked below, at 1000 meters, the standard barometric pressure would be ~730 mmhg.  Given a bit of fluctuation due to weather, it looks like it could be actually somewhat close to expected pressure.

So, I am not sure why you were expecting 660 mmhg (that would equate to about 4000 m).  But, I think your presumption of what the barometric pressure should be was incorrect.

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