RV Water Heater – 7 Important Things You Need To Know

Water heater

It may not be very exciting to look at but your RV water heater plays one of the most important roles in your rig. From preventing frigid showers, to ensuring your dishes are safely cleaned, that little appliance does some big work. Here are a few things to know about your water heater for RV.


  1. There are three basic ways an RV hot water heater works. You can have an RV water heater that runs on propane, electricity, or heat from the engine. Electric RV hot water heaters are the most common and convenient, because you can turn them on with just a flip of a switch. Using heat from the engine is the most economical because you’re using heat your rig is already producing while driving. However, if the engine has been off for a while, your water may not get as hot.
  2. RV water tanks come in several sizes. 6 gallon RV hot water heater tanks are one of the most common, along with 10 gallon RV hot water heater tanks. Tanks can be as small as 4-gallons, or as large as 16-gallons. The more people you’re traveling with, the larger a tank you’ll want so you don’t run out. 

You’ll notice that a hot water tank for RV is much smaller than a home hot water tank – a small home tank is 40-50 gallons. When using an RV water heater, be mindful of conserving water! Take shorter showers, turn off the water while shampooing, and generally save water when you can.


  1. If you’ll be storing your RV, make sure to drain the water tank first. If you’re storing it during winter, winterize the pipes so they don’t freeze and crack. If your RV hot water heater operation has a bypass valve, make sure to use that during winter as well. 
  2. Remember to turn off the bypass valve when you use your RV again. The tank needs to fill back up before you leave on your trip. Heating up the tank with no water in it can damage your system.
  3. Install an anode rod to avoid hard-water corrosion inside the tank. The corrosion will attack the rod instead of the tank. They’re an easy installation, but you’ll want to check it from time to time. If it looks corroded, replace it with a new one. Rods are usually under $20 and can definitely extend the life of your tank. 
  4. If your hot water heater for RV is installed and in working condition, but your water is still lukewarm, make sure the hot and cold faucets to the outside shower or water line are off. Leaving them on can cause the hot and cold water to mingle, keeping your water from getting properly hot inside. 
  5. You can also consider purchasing a used RV hot water heater. Used RV hot water heaters are sold online on places like eBay, Craigslist, or the Facebook marketplace. If you’re unfamiliar with RV hot water heaters, have a professional check it out to be sure you got a good deal. eBay has a return policy if the product you purchase does not turn out to be as promised.

RV hot water heaters are an important part of any journey you take in your rig! We hope you’ve learned a little more about how they work and what to look for when buying one so that you have all the heated water you need for your travels.

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