Specs questions for 320 & 400’s.

shane1 said:
. . .  AC BTU’s of both models?

Newer model year 320S have the Air8 air conditioner, a ducted delivery design, with ~ 6K BTU.
Older model year units will have a "window style" air conditioner with ~5K BTU.

Newer model year 400 have a CoolCat, a ducted delivery design, with ~ 10K BTU.
Older model years have a mix of different air conditioner types . . each used rig would need to be researched.

. . .  Alde radiant heat BTU’s of both models?

Both the 320S and 400 use the Alde 3020HE boiler which is rated at 11K & ~18K BTU depending on user setting of boiler heat source.  However, since this is a 'radiant' heat delivery system direct comparison to forced air furnaces in all other RV brands is not easy.

Quantity and placement of the Adle convectors (similar to a steam radiator but smaller, lighter, and hidden) are the real factors on overall cabin air temperature comfort.

Simple reference:

. . . Are both able to keep the warm and cold with the supplied HVAC?

Keeping in mind that the TaB 320S and 400 are three-season not four-season trailers the basic answer for most users is Yes, nüCamp did a good job in sizing the two systems for these trailers.

Of course we all have different comfortable temperature opinions and some earlier model years of the 400 did have air conditioning power issues.

For myself the Alde System is wonderful; quiet, comfortable, reliable - - - once you master the Control Panel