Water Heaters: Replacing the Dip Tube

Dip tube is a part of a water heater unit. It is connected to the cold-water inlet at the top. The water enters the heater through this tube and collects at the bottom. It is long and hollow with double threads at one end to fix it. The cold water comes in contact with the thermostat at the bottom that triggers the ignition mechanism at the appropriate temperature. This is where the heating element is usually placed and the water gets heated. This hot water moves to the top of the tank where the hot water outlet is provided. This outlet distributes it to your hot water appliances.

One of the symptoms which indicate improper functionality of your water heater is getting lukewarm water instead of hot water. When this happens, start your troubleshooting with the dip tube. It might be fractured somewhere along its length. Usually, as soon as the integrity of the dip tube is compromised, the cold-water escapes from the hole, crack or a break and starts mixing with the hot water, thereby reducing its temperature.

If you are feeling brave, you can open the unit up by yourself, try to replace this dip tube with a brand new one. With a little technical knowhow and guidance from us, you can do this easily. Now then, let’s begin.

Turning off your water heater

“I know this already, let’s move on!” Sure, O’ hombre valiente; but if your gas heater explodes in your face or electric heater gives you a hair raising experience, you’ll find it quite difficult to achieve your goal. To avoid that, first find out where the circuit breaker or on/off dial on your electric or gas heater is, respectively, turn them off and ensure that the heater unit is not operational.

Turn the cold water supply off

Removing the dip tube will, no doubt, splash some residual water all over the place. It is better to work under dry conditions, unless you want to get all wet to show off how hard you are working. In any case, to turn off the cold water supply, find out the cold water inlet. Then, find the knob or a lever that operates the cold water supply valve, usually located before or above the inlet and turn it off by rotating or moving the knob or lever in the specified direction.

Draining the tank

To make sure that the tank is completely empty before you dismantle anything, you need to drain the tank. A drain pipe with a valve is usually provided at a suitable location. Operate this valve (or open it) by the knob or a lever and drain out all the water from the heater. If the drain valve is absent, open up one of your hot water appliances and fill up some utensils or buckets with that water (why waste it?) until the entire heater system is devoid of any water.

Cutting the dip tube

Are you ready to get your hands wet and dirty? Right then. Now would be a good time to open up your user manual and try to find out the section where this procedure is mentioned. Have a cutting tool handy, just in case. You may need to cut a part of it and remove the remaining attachment from the lower inlet if the attachment is rigid or soldered. If you do cut the pipe and find out that nothing was wrong with it, then you will have wasted a perfectly good piece of equipment worth 6 to 10 bucks. But that’s a risk worth taking if you are reluctant to call a professional for any reason. If the arrangement screwed on with the double thread mentioned earlier, it will be easier with a socket wrench and you might not need the cutting tool at all.

Once the pipe is removed, check for cracks, corrosion, calcium deposits, breaks or chunks falling off. There are instances when the entire threaded end of the dip tube might land in your palm! If any of these conditions exist, you need another dip tube and a visit to your local hardware store is mandatory.

Out with the old, and in with the new!

So you have your shiny new dip tube with you, ready to begin its duty. Before we actually get on with the installation, there are a few things you can do to make this maintenance easier. If you were paying extra attention to the task of removing the old dip tube you would have noted down the difficulties you faced. If you did, kudos! If you did not, be prepared to go through this fantastic process once more, the next time this happens.

Anyway, if you needed to cut the upper part of the tube, then it was probably connected to the main piping made of some metal (copper, most of the time) with a solder or a weld. You can do the same and weld the new dip tube to the main piping. This is a rigid setup, called ‘coupling’ which ensures stability and prevents leaks. But as you guessed, you have to throw it away on removal or waste your time tinkering about and welding the piece back on.

Instead, a little plumbing knowledge will reduce your hassle by a tremendous amount. In plumbing terms, there are various concepts that exist in the piping which make it easier to connect longer sections of the pipe. These make the plumbing process highly modular; and are crucial in routing the entire system around any place.

[How to Hire a Plumber? The Top Tips]

One such concept is the ‘Union Fitting’. It consists of a hexagonal object that looks very much like a nut which is screwed on a bolt. The difference is that its hollow portion is threaded (female threading) on both sides. If you have a plumber friend, cut a section of the main piping with your pipe-cutter. Then have your friend thread the lower end of the main piping and both ends of the cut section. This way, you have a ‘middle-man’ between the main piping and your dip tube with union joints on both ends. Now you will be able to remove and reinstall the dip tube as many times as you want. This little trick will make it a lot easier on you to perform subsequent maintenance tasks on the dip tube.

The direction and length of the threading plays an important role in this fitting. The threading on the main piping is usually longer in length to allow easy traversal of the union fitting. It is also subject to wear and tear, but the maintenance cycles are spread quite far apart to affect the joint in any adverse manner. Besides, the fitting and dip tubes are highly affordable; so getting them replaced will only cost you some time, if at all.

Confused? Call a professional plumber immediately and be ready to shell out a hefty hourly cost.


Assuming that you have adopted the threaded union fitting approach, you need to follow these instructions for a proper installation:

  • Clean the threads on each piece of the connection and wrap the threads of the main pipe, the ‘middle-man’ section as well as the dip tube with a good quality Teflon tape.
    “What’s that now?”
    It is a way to ensure water-tight fitting on both sides to prevent any leaks. This tape should be wrapped in the general direction of the threads. If you are unsure of the directions, think about the direction in which you will rotate the union joint to tighten it.
  • Then insert the dip tube in the slot provided on the water heater, and rotate it so that the lower threaded section fits properly with the threaded socket at the top of the water heater slot. Use a suitable wrench if necessary.
  • Then position your ‘middle-man’ section between the dip tube and the main piping. Tighten the union joints until they are tight.

Fire up your heater, wait for it to reach operational capacity and check for leaks wherever there are joints. If there are no leaks, check the temperature of the water coming out of the faucets of any hot water appliances you may have connected to the water heater. If you get your expected results, then congratulations! You have just replaced your dip tube successfully!

DIY or ‘Do-It-Yourself’ is not that difficult!

IF you have access to all the required information as well as knowledge of using that information to get your job done. With the power of internet, Google or DuckDuckGo and the correct keywords, the only person stopping you from maintaining your household, is yourself. Anyone with a computer, smartphone or a tablet can access this information at the click of a button. There are experts all over the world with informative articles and videos showing exactly how things are done. Quite literally, anyone can become a DIY enthusiast. This territory is no longer restricted to ‘boys and their toys’.

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