Okay, you've filled up the RV water tank and hit the switch to pump the last of the antifreeze out of the plumbing lines. 

The only problem is... the RV water pump just keeps running and won’t shut off.  The water flow is only a matter of a few drips at best. 

Now what?

RV water heaters are generally pretty reliable.  Under normal conditions, they’ll last a good long while with very little attention. 

There are a few ways a water heater can develop a leak, though the most common is due to negligence or operator error:

Failure to drain the water out of the tank before the first winter freeze would rank as the most common mistake.  You can empty the water tank, drain everything else, but if you forget to take the drain plug out of the water heater it won’t drain.  After the water freezes, the aluminum tank will split wide open. 

Another problematic time is the first time in the spring when you're anxious to get going on that first RV trip of the season.  If your water heater is equipped with a bypass kit (hoses and valves that stop water from entering the water heater) and you forget to open the valves allowing the tank to fill, you're in trouble. If the burner is ignited and the water heater is empty of water, the temperature in the tank will rise to dangerous levels, possibly melting a hole in the tank. 

One final scenario would be corrosion inside the water heater.  This can be caused by hard water.  Over time, the water eats away at the aluminum tank and eventually it will develop a leak.  This condition can be prevented by installing an anode rod.  The corrosive reaction will eat away the anode rod and leave the tank alone.

The anode rod is attached to a replacement drain plug, making installation as simple as removing the plug and screwing in the new plug/anode rod combination. Plus, every fall when you drain the tank, you will be able to see how well the anode rod has been working and determine whether the anode rod is still in usable condition or not.  If it has dissolved away, you will know to buy a replacement one before the next time you use your RV. 

We’ve covered the most common failures of the RV water heater’s aluminum tank, now for the cure. 

Wouldn’t it be nice if all manufactured products never wore out, or failed? 

Unfortunately, in the RV world -- due to weight or cost restrictions, and of course exposure to the elements -- some RV components have a higher failure rate than what you find in the average house.

Many of the following RV repairs can be avoided altogether with proper RV maintenance and storage procedures.