View Full Version : Replacing the water heater's electric heating element

05-02-2010, 12:23 PM
There is no trick to replacing the electric heating element, but some of the steps are not obvious. So let's see if this helps.

Your water heater is almost certainly a Suburban SW6DE, and if so, the replacement heating element has Suburban part number 520789. RV parts places may have replacements that are not from Suburban, but are labelled as equivalent. These are a good solution.

Tools needed (first photo): in addition to the new element, you will need a straight screwdriver, a Phillips screwdriver, a water heater element wrench (buy one at the same time you buy the element, or at any hardware store), and a 7/16-inch open end or combination wrench. A 1/4-inch nutdriver may be handy, but is not required.

Start by disconnecting shore power and draining the water heater. Then, take the outside cover off the water heater. You should see what is in photo #2 below.

First, look at the lower left corner of the photo. You see the silver tube that is snaked around, and goes into the large brass burner tube? Using the open end wrench, carefully back off the brass nut that is right where the silver tube joins the brass burner tube. Don't pull anything apart yet - just back off the nut until it comes off the connector. You'll see a brass collar on the silver tube - don't attempt to move it. And don't touch anything inside the square opening that is cut into the burner tube. [Note - later versions of this heater have a slightly different configuration and you don't have to mess with the gas burner tubes in order to get access to the electric element. Nice change.]

Next, look at the right end of the brass burner tube, after it has made the 90-degree bend near the red wire. Protruding from the bottom of the tube is a threaded screw with a nut on it. Again using the open end wrench, remove that nut completely, and set it aside where it won't get lost. You can now gently jockey the right hand end of the brass tube upward until the threaded screw comes out of the hole, releasing the tube. Pull that end of the big brass tube toward you just a little until it is free.

Once you have done that, move the entire brass tube gently to the right until it slides off the snaked-around small silver tube. Try not to bend the snaked silver tube, though you may have to flex it slightly to get the brass tube off it. Set the brass burner tube aside in a place where it won't get dinged, dented, wet, etc.

With the burner tube out, you have access to the black plastic cover (photo #3). It is held in place by three screws, two of which are easy to get at, and one of which will fight you a little bit (this is where the nutdriver may help). Remove those three screws and take off the black cover. At this point you are looking at the electrical connections to the heating element, as shown in photo #4. YOU ALREADY DISCONNECTED SHORE POWER, RIGHT??

Back off the two electrical screws, remove the wires, and push them out of the way. At this point, it is worth confirming that the element is actually bad. No point in replacing a good element, right? If you have an ohmmeter, the resistance between the two screws should be 10 ohms or so if the element is good, or very high/infinite ohms if the element is bad. If you don't have an ohmmeter, but do have a battery-powered test light, the light should light when you put the probes on the two screws of a good element - it will not light on a bad element.

Next, use the water heater wrench to unscrew the heater element. You will need to put a long screwdriver or rod through the pair of holes in the round end of the wrench (they are not visible in photo 1) in order to turn it. It comes out reasonably easily. Note that there is a rubber washer or gasket on the threads of the element. When you install the new element, make sure that the old rubber gasket has been removed and discarded, and that the new element has the new gasket in place. In other words, when you screw in the new element, there should be exactly one gasket.

Optional. With the element out of the hole, you have an opportunity to peer inside the tank. Using a flashlight, you can look at the condition of the anode rod. If it is pretty well corroded away, it is time to replace it. You can also look for silt or sand sitting on the bottom of the tank. There will probably be a little, and that's OK, but if there is a lot, this is a good time to get it out.

Screw the new element into the hole by hand, and use the water heater wrench to tighten it. Remember, one and only one gasket. With the new element screwed securely in place, re-attach the electrical wires - it doesn't matter which wire goes to which screw. On mine, one of the wires was really short and hard to reattach. If one wire won't reach, it may help to tighten the element an eighth of a turn to reposition the screws. Once the wires and the black cover are screwed on, reassemble the brass burner gently, again striving not to bend the silver tube.

That should do it.