RV Repair Manual
for the RV Do-It-Yourselfer
There are basically two manufacturers of RV water heaters that are used in todays RVs - Atwood and Suburban. The Atwood uses an aluminum water tank while the Suburban brand uses a glass lined steel water tank. Maintenance and servicing procedures are similar to both models.
The arrow shows the drain plug on an Atwood - a Suburban water heater will have an anode rod rather than a simple drain plug. This anode rod helps to prevent corrosion of the steel tank and should be inspected annually and replaced when necessary.
I do recommend flushing the hot water tank occasionally to get rid of the sediment and corrosive deposits in the bottom of the tank. Just pull the drain plug, allow it to drain, and direct a stream of water into the drain hole to agitate the sediment. Then allow it to drain, repeat until the water comes out clean. Do this about every other month (or more if your water has a lot of minerals) The flushing also helps to eliminate any hydrogen sulfide that may build up in the tank (causes the rotten egg smell in the water), and makes the heater more efficient.