12 volt computer fan hooked up to fan electrical connections on back of freezer. I used foil tape to close off some of the openings in that cabinets to create a colder larger stream of air over the condenser tubing. I have the fan mounted high up inside the sink cabinet with air flow vented into sink cabinet.
Nodak, I am with you about the poor insulation and performance of the nova kool freezer. I have been unable to find a drop in replacement. The extra fan does make a difference. Short of chopping up the interior, there really is no good freezer solution that I have found.
My challenge is every summer when we fill the boat with adult kids and +1,s we run out of soda and beer space. I would really like to have a back up fridge just for drinks......yes I understand the power needs.