Close this search box.

Water Heater Dip Tube Explained

Note: This post may contain affiliate links. This means that at no cost to you, we may receive a small commission for made purchases.

If you make a list of the essential appliances in your home, you’re sure to land on your water heater in the top few rankings.

It makes your mornings comfortable by providing you with cozy hot water. On the other hand, this same water heater is one of the least energy-efficient appliances you can own.

It is essential to know and control your water heater usage to prevent the occurrence of outstanding electricity bills.

Principally, most water heaters contain a dipped tube inside their tankers that regulates the flow of cold water to the bottom. Once the cold water settles on the bottom, the hot water rises to the top.

The dip tube prevents the cold water from merging with the hot, giving you continuous hot water in your shower. Let’s find out the functions of a dip tube inside the water heater in detail.

What exactly is a water heater dip tube?

what is dip tube

A typical dip tube attaches to the cold water inlet of a heater and runs up to roughly 8 inches of the bottom of the tank.

It is a long plastic tube that brings in cold water and pushes it to the bottom of the tank, where the gas burner or any other thermal device heats the water. The dip tube is also responsible for preventing cold water from mixing with water that’s already been heated.

When you open the hot water faucet in your shower (see also ‘This Is What You Need To Do When Your Shower Faucet Won’t Turn Off‘), the pressure inside the plumbing pushes cold water down the dip tube. Simultaneously, the force also pushes the hot water from the tank into the hot water faucet.

You’ll know that your dip tube has stopped functioning at full capacity when you begin to lose hot water fast. When the dip tube is not working, it will allow cold water to mix with the hot water and effectively cut down on your steamy hot shower.

You should know that water heaters with their cold water inlet on the bottom do not have a dip tube. In fact, they don’t need one.

Life of a Dip Tube

how to replace dip tube

Your dear water heater has a lifespan of 10 years, give or take a couple. A dip tube fixed inside this heater should ideally work well throughout the heater’s lifetime, as mentioned above.

However, a dip tube will give you clear indicators when its time is up. You’ll get shorter spells of hot water, or you might even get lukewarm water instead of your usual steamy bath.

There are also chances that something might malfunction within the heater and cause distress to the dip tube. This malfunction can be attributed to the dip tube breaking inside the tank.

In fact, tubes made between 1993-1997 were infamous for their weak nature; they were made from low-quality polypropylene plastic. You can check if your machine has a dip tube from this era by checking the serial number.

However, if you own a device from the 90s, it is probably a good idea to replace it now. These dip tubes often broke or disintegrated quickly and would create small white plastic particles which could clog your plumbing (see also ‘3 Main Types Of Plumbing Cleanouts You Should Know‘).

Dip tubes also have a poetic and dramatic function; they are sacrificial anode rods. They attract all corrosive elements in the water, protecting the heater tank in this process. Hence, the dip tubes ultimately sacrifice themselves for the benefit of the whole heating system. This sacrifice often shortens the lifespan of a dip tube, as it is prone to corrosion.

Using hard water can also decrease your dip tube’s lifespan significantly. Hard water contains more undissolved minerals, which can potentially corrode the dip tube faster. The corrosion can lead to the disintegration of the tube.

Sometimes, the dip tube can also detach and shift its position inside the tank, and a disconnected dip tube can be responsible for cold water mixing with hot water.

A handy tip – fish out your heater tank once a year to reduce the risk of sedimentation and corrosion on the bottom of the tank.

Replacing a faulty Dip Tube

If your dip tube is troubling you, you can replace it with ease. You can always call your plumber for the same, but replacing a faulty dip tube is not very difficult.

Turn off your water heater first. Break it away from the electrical circuit of your home. It is to ensure that you won’t electrocute yourself working on the faulty tube. Next, you need to turn off the cold water inlet.

Since dip tubes bring in cold water to the bottom of the tank, shutting down the cold water inlet will make dip tubes stop their work. Also, don’t forget to disconnect the main water supply to the heater. Now that you have immobilized your heater and its dip tube, you can move ahead.

Let’s say that your dip tube broke inside the heater tank. In that case, your best choice would be to drain the hot water outlet. Doing this will remove any bits of plastic stuck in your pipes or faucets.

Now comes the critical part. You need to gently remove the short piece of pipe threaded at both ends to expose your dip tube. Remove the tube using a flat screwdriver. You need to remove it very slowly since it will have a significant amount of rust on its surface.

Next, drop a new dip tube into your heater tank. A cross-linked polyethylene (PEX) tube will work best and not disintegrate inside any water heater tank.

Reconnect the main water supply line to the heater, and refill the tank with the hot water faucet open in your bathroom. Doing this will release any air stuck in the heater system. After a few minutes, you can power on the water heater tank once the air is out. Finally, do a quick check to see if the new dip tube is working well.

A new dip tube costs approximately $10, and having a professional fix you up with a new one can cost somewhere around $150.

New Tech in Dip Tubes

function of the dip tube

Multiple companies like AO Smith, Rheem, and Bradford White manufacture dip tubes for water heaters.

Each company uses proprietary and patented technologies to make its tubes. Up-and-coming tech in dip tubes makes them less prone to corrosion and solves other tube-related problems too.

AO Smith uses its Dynaclean technology to manufacture cross-linked polyethylene (PEX) tubes. These tubes have a stronger resistance against water temperatures and can withstand all kinds of impurities they might have to face.

Another major player in the Dip Tube market, Bradford White, makes the Hydrojet dip tube. This flamboyantly named dip tube has a series of concentric ‘jet ports’ that create turbulent action inside the heater tank.

The primary function of these jet ports is to redirect water flow inside the tanker with dynamic action. Keeping the water flow moving ensures that impurities will not settle on the tube or the bottom of the heating tank, keeping it safe from corrosion.

Closing the faucet on Dip Tubes

After this extensive lesson, we have learned quite a few things about the phenomena that are Dip Tubes.

One can say they’re the esophagus for a water heater tank, doing the crucial work of taking cold water and bringing it to the heating apparatus. It is also clear that these dip tubes are made to stay inside the heater tank for the entirety of the machine’s lifespan.

However, this is not always the case. Many-a-times, dip tubes malfunction and even need to be replaced in certain events. The dip tube may start to crack or leak, making it useless in the tank. Sometimes, if the tube is not made of good plastic quality, it can even break inside the tank.

You’ll notice these happenings in your shower when the water feels like it is not as hot as it was before. Alternatively, if the tube has broken inside the tank, then you might find pieces or sludge of white plastic in your faucets, often blocking the plumbing.

Replacing the Dip Tube is the best option in these cases. However, if you plan to do the plumbing job yourself, you must take utmost care and try not to get electrocuted.

Make sure you follow all safety guidelines related to water heaters. It would be best to drain the hot and cold water inside the heater tank carefully and thoroughly before working on dip tubes. You should also handle the corrosion on the tubes well.

Fret not. Dip tubes don’t have to be replaced very often. In fact, the tubes themselves are inexpensive, and major players in the plumbing market are working to make water heater tanks safer for you.

They are constantly developing tech that has the potential to increase the lifetime of the dip tubes in your water heater tanks.

You can choose the best water heater for your home from a variety available in the market today. Make sure you buy the one with the most extensive lifetime so that you get the longest-lasting dip tube.

author avatar
Charlie Hardcastle


On Key

Related Posts

Is Drano Bad for Pipes? The Truth Revealed

Note: This post may contain affiliate links. This means that at no cost to you, we may receive a small commission for made purchases. When it comes to dealing with clogged drains, many homeowners turn