How to set Suunto Zoop to permanent Nitrox

[Centrals]

If you dive Nitrox at all the manual, and probably most users, suggest putting the computer in "Nitrox" mode and leaving it like that all the time.

regular air == nitrox 21 == plain air
When someone talks about their Zoop (or similar models) resetting to regular air, they are talking about the percentage changing on them. It is a pretty well known behavior.

Zoop's user manual p.43
Default Nitrox Settings:
Manually entered values of O2 % are retained for about 2hrs after the setting if a dive series has NOT STARTED. In case a dive series IS STARTED, the set value is RETAINED until a NEW DIVE series is started or a NEW VALUE is entered manually.

What is the definition for new series in this case?

 

[JohnN]

Zoop's user manual p.43
Default Nitrox Settings:
Manually entered values of O2 % are retained for about 2hrs after the setting if a dive series has NOT STARTED. In case a dive series IS STARTED, the set value is RETAINED until a NEW DIVE series is started or a NEW VALUE is entered manually.

What is the definition for new series in this case?

Once you clear your "no-fly" interval, the computer considers it a new dive series.

FWIW, I rechecked my Vytec (non-DS) and it (as well as my Vyper Air) retains the EAN setting (its been almost a week now)