There are a couple of other factors involved in keeping the refrigerator cool.
There needs to be good air circulation inside. If you pack it too full, it won't cool well. If you have large items blocking air circulation, it won't cool well. An interior fan
like this one will help.
With a residential refrigerator, we all will open the door(s) and stand there trying to decide what we want. With a traditional RV gas absorption refrigerator, this will cause a significant temperature rise which can take many hours to recover from.
If there's anything too large inside, creating outward pressure on the door(s), you'll have air leaks around the seals and it won't cool.
If anything is restricting airflow outside at the louvered vents, it won't cool properly.
Many refrigerators come with fans mounted on the backside to move more air across the heat exchange tubes. If it's hot out, and you don't hear fans when standing outside, you may want to have fans added.