RV water heater maintenance is pretty straight forward. With a few tools, a warm sunny afternoon and a little know how it’s easy to do it yourself. The main thing we want to do is flush out the sediments and deposits that build up over time in the tank and replace any corrode parts.
There are two big manufactures of HW tanks for RVs. They are Atwood and Suburban and the big difference between them is Suburban uses an anode rod and Atwood doesn’t. An anode rod is made of aluminum or magnesium and designed to be a sacrificial element. Meaning instead of the tank corroding away the anode rod does instead. My Keystone Cougar fifth wheel has a Suburban SW6DE HW heater installed in it so the following article and video will describe my routine yearly maintenance on that particular model.
First Things First – Safety!
Most RV Hot Water Heaters use both electricity and LP gas, so extra precautions are required when working on them. If you’re at all uncomfortable doing it yourself, please stop and get a certified technician to do the job for you. I’m not an RV Technician, just a dedicated RV enthusiast who likes to learn and perform my maintenance tasks. Take what I say with a grain of salt.
Shut off the electricity to the rig. I like to unplug all power cords, turn off the HW heater breaker and power switch. Turn off the gas and power switches and all LP Gas cylinders. Then make sure the water in the hot water tank is cool. The easiest thing is to have a shower or run a tap until it is coming out lukewarm. Open the safety release valve located at the top of the tank and let the pressure equalize. With these steps complete it should be now safe to pull the anode rod.
Removing the Anode Rod
The anode rod in my Suburban SW6DE requires a 1 1/16th socket to remove it. I use a deep socket with a small extension and my torque wrench to perform the task. Sometimes the anode can be rusted in place, so the extra length of the torque wrench helps. I position a couple of large plastic bins below the HW heater to catch the debris-filled water. Wear some old clothes because when you pull out the anode, the water will come out pretty fast at first and likely will include lime scale and debris.
If the anode has been in there a while and the camper used a lot, it will probably show signs of corrosion and look eaten away. Which is a good thing; it means it is doing its job.
Give the Tank a Good Flushing
Now that the tank is empty it’s time to get the fresh water hose and hook it up to a flushing wand. The flushing wand is designed to reach way back into the tank and has a narrow tube to increase the water pressure.
Keep flushing until no more calcified deposits and sediment come out. I like to jam it way in there and block off the entrance a bit, so it fills the tank up and then let the power of the escaping water help flush things out.
Checking the Electric Heater Element
At this point, I also like to pull out the electric heater element and have a look at it. I travel to some areas with very hard well water and I know that deposits build up on the element. One way I know this is I can hear it singing when it is heating up sometimes. It makes a high pitched noise as the water is heated.
Unlike the anode removal, the electric element removal is a little more involved. You have to remove the LP Gas burner tube and undo some electrical wiring to get it out. Like I said earlier if you feel at all uncomfortable doing this type of work yourself then have it done by a professional. Better safe than sorry. Also, you may want to check if you will void some kind of warranty by doing it yourself.
The gas burner is removed by loosening a couple of 7/16th-inch nuts. One holds the burners end in place and the other attaches the gas tubing to the supply line. Remove them and gently wiggle the burner tube free. Once the burner is out of the way it gives access to the three flat head screws holding the electric elements plastic cover. Remove this to expose the element and its electrical wiring. Then with a Philips screwdriver remove the two AC wires from the element terminals.
To remove the electric heater element, you are going to need a special wrench. It’s a 1 1/2 inch socket with a very thin wall designed to get into the recessed nut. With the aid of a screwdriver for leverage unscrew and remove the element. Once it’s out, inspect it for any corrosion and deposits.
At this point, you can decide if it’s in good enough shape to re-use or replace. This time around I decided to replace mine as it had clear evidence of rusting going on near its base. The heater elements are relatively inexpensive.
So in goes the new electric element. On go the electrical wires, plastic cap, and LP Gas Burner. Be careful with the gas burner connection. You don’t want to over tighten the brass nut. Also once you have finished the remaining HW heater maintenance steps, you’ll want to test it for leaks with a soapy water homemade solution or a commercial spray. The gas will have to be on, and HW heater fired up so that this line has pressure in it.
Refill and Test the RV Water Heater
I like to install a fresh anode rod every year. I take the new anode rod and wrap white Teflon plumbing tape around the threads and screw it back in place. Once it is in there nice and tight, it’s time to turn the water back on and let the HW tank refill.
You should hear it pour into the empty tank. As it fills, you can use the pressure relief valve to let the air escape. Then go in and turn on your hot water taps and let them run until they stop gurgling and run freely.
Now it is safe to plug the trailer power back in and turn on the HW heater breaker and power switch. I can test if my electric element is working right away by utilizing the AC current readout on my Progressive Industries surge protector remote display panel. With the element turned on it reads an additional 10 amp load. The water should begin to show signs of heat in 20 minutes or so. While waiting it is a good time to test the gas connection and burner operation as well. Finally, monitor the hot water tank for any leaks over the next few days.
Video Detailing My RV Water Heater Maintenance
Tools Required and Replacement Parts
- Anode Rod Part # 232767
- Electric Heater Element Part # 520789
- 1 1/16 Deep Socket
- 1 1/2 Special Element Removal Wrench
- Tank Flushing Wand
- Teflon Plumbing Tape
There you have it, my yearly RV water heater maintenance routine. In between this full maintenance, I will usually pull the anode a few other times during the year for a quick flush and check. This also helps stop the anode from rusting in place like they can do if left in too long.
One thing that I have never had to do myself but hear works really well to clean a heavily gummed up tank is vinegar. You empty the tank, then re-insert the anode rod and pump a few gallons of vinegar into the tank with the RV winterizing kit. Fill the rest with water, heat it up and let sit for several hours or more. Then give it a good flushing. The vinegar should eat away the scale and deposits.
Update – I recently tried the vinegar trick with great results. See the blog post and video.