RV appliances are not like residential appliances at all. They have a lot of switches and valves that get dirt in them over time. They sit for long periods.
It is good to get familiar with all of your appliances and to do the maintenance on them to the extent possible. When I get frustrated with some of these odd contraptions, I call a mobile mechanic that comes to the house. They go right to the problem in 20 minutes and can fix everything usually in less than an hour. I have only spent more than $50-75 once to have a guy replace the cable in a pop-up trailer. They are like magicians and can make life easy. Find a guy that specializes in RVs.