RV service calls are expensive and many of them can be avoided.  When repairing an RV, I often hear “Oops, wish I knew that!” when I explain the issue could have been avoided.  At risk of losing business, and keeping with my theme of “RVing should be fun, not frustrating”, here are 4 things you should do (or not do) to avoid calling a costly mobile technician: RV refrigerators have to be level. Most RV’s have an absorption style of refrigerator. They can run on either 120 volt AC and propane. They heat a chemical liquid in a tank that turns to gas, which rises to the upper back of…