In 65-75% humidity or more unit will start to form 'fog' and then 'water' on outside of glass door, this is normal is glass door fridge operation, and cannot be controlled.

These Rhino units have special 'Double Layered LOW E' Glass which allows them to be much more resilient to condensation forming, whereas normal glass would condensate at 50% RH.

The only way to stop this happening is to have a unit with 'heated glass', see model SG2H-HD and soon to be released June 2017 the Rhino ENVY series (ENV1R-SS, ENV1L-SS, ENV2H-SS, ENV3H-SS).

*Read more about condensation at this link;
https://www.bar-fridges-australia.com.au/the-facts-about-condensation-on-glass-doors-of-bar-fridges.html