There could be several causes for the problem you are experiencing with your RV water heater. The problems could range from a bad Thermocouple, obstructed main burner, obstructed exhaust grill, poor propane supply, etc.
Some the items mentioned above can be resolved by performing routine maintenance on your water heater. The first thing you should do is watch the video below by RV Expert Mark Polk from RV Education 101, it gives you the proper steps to maintain your Water Heater, if these steps do not help then you are going to have take your RV in and have the water heater checked out by a Certified RV Technician.
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