Is there any other place than The Chill in Skyrim with unsummoned atronach?

I am making an atronach replacer for Skyrim and I need to test whether my mod replaces all atronach summoned by another NPC or unsummoned (already placed as a monster in the map). Is there any other place or place where they get are scripted to appear without a NPC casting it?

Solution 1:

Flame Atronachs can be found

• roaming Skyrim and in dungeons occupied by conjurers, or during random encounters.

Frost Atronachs:
Apart from The Chill,

• one can be in the summoning chamber of Cragwallow Slope if at an high enough level,
• three can appear in The Caller's chamber in Fellglow Keep during the College of Winterhold's questline.
• Otherwise, Conjurers, Thalmor Wizards and Draugr Scourge mages have the ability to summon the atronachs.

Storm Atronachs

• can be found in the wilds, and are also commonly summoned by Dragon Priests.

Considering this, it'd be easier to 'summon' a couple of Dragon Priests and conjurers using the console:
Type player.placeatme <BaseID> <#>, where '<BaseID>' is 00023A93 for Dragon Priests, 000728AD for Thalmor Wizards, 00023BF7 for Draugr Scourges, and 0001091A for Arch Conjurers. '<#>' is the amount of NPC's you want to place.
Be sure to toggle God Mode with tgm :)

You might also want to check whether the standard Atronachs have been replaced using this console command: 00023AA6 is for the Flame Atronach, 00023AA7 for the Frost variant, and 00023AA8 for the Storm Atronach.