If your camper has accumulated an odor, or you just want to freshen it up before a trip, I recommend the ForeverOzone generator (Amazon Link below).
Ozone is a great (natural) way to remove food, pet, mildew or smoke odors from inside your Camper. Simply plug in the Ozonator and a breeze box fan to circulate the Ozone for an hour or two and your Camper will be fresher than New! Note: Ozone is excellent at removing that "New Smell" from carpets and other materials used to build your Camper.
I have successfully used Ozone in our rental homes for years to remove Smoke and Pet odors left behind by Tenants.
Note: Ozone has it's own odor (which totally dissipates) so, let your Camper air out or sit overnight before performing your "Sniff Test".