How To Replace A Sacrificial Anode

Just about every storage water heater tank has a sacrificial anode rod and if you have one at home knowing how to replace a sacrificial anode for your storage tank hot water service is a very easy and simple job.

It can and will increase the life of the system which means long term savings for you and because they sit inside the tank you can’t see them until its to late.

Many homeowners are not familiar with doing any water heater repairs or routine checks to them.

One of the most important parts of a water heater is the sacrificial anode rod and how to replace the anode is easy to do.

What a anode does is it sits inside the unit and attracts the bad particles that’s in the water that could otherwise attack and corrode the tank shorting the life of the heater system.

Below is my method on how to change a water heater anode or sacrificial anode rod also what there called.

Types Of Sacrificial Anode Rods

There are a few different types of anodes made differently with different materials for different needs. Even motors on boats have anodes but for hot water tank all we need is just a standard sacrificial anode rod from any hardware store. I’m not going to get into the nitty gritty of what a anode is made of for most of us we don’t need to know. All we need to know is which one we need when replacing which one to buy and how to install it. The 2 main rods are solid anode rod and flexible anode rod.

Flexible Anode Rod

Flexible anode rod is used where there is a limit of height above the location of the hot water tank.

Where this can happen is when the hot water service tank is installed external under an eaves line of the roof or internally on a low hanging ceiling in a subfloor as such.

They’re a one-piece rod still but on the rod are sections where you can bend the rod and won’t break unless you keep bending it will but on a normal install it won’t. The standard length is 44″ or 112cm. See the picture  on how a flexible sacrificial anode looks

Standard Anode Rod

Standard sacrificial anode rods are the more common water heater anode rod out of the 2.

The length is the same as a flexible rob and install is the same.

With this one tho we don’t have to straighten the rod as we are lower and install it into the tank as there will be room overhead.

Removing The Sacrificial Anode Rod

Things That You Will Need
  • New Sacrificial Anode Either Flexible Or standard Rod
  • Plumbers  Teflon Thread Tape
  • Socket Wrench And Socket To Suit Anode Rod Nut
  • A Breaker Bar-Or Extension Bar Just In Case Need More Leverage

Step 1- Turn the water off- Make sure you turn the water off. There should be a isolation valve at the water tank or to the property. If you need more info about how to do that then check this out. It will give you a guide on how to isolate your house water.

Step 2- Release the pressure- Once you have turned the water off open up a hot water tap or pull open the pressure-temperature relief valve (PTR) until water stops coming out.

There won’t be a lot of water so it won’t take long. What this will do is release any pressure that is inside the water tank.

Step 3- Turn heating source off- Once you have turned the water off to the system then I recommend turning the heating source off.

Depending on your own ability as it won’t take long to change over and if you have a gas heater it may be easier for you to leave on saving to trying to light that pilot light once completed.

Step 4- Sacrificial anode rod removal –  On top of the tank there may be a plastic cover plate. Under that plastic cap is the anode nut.

Pop the cap off and you will see a big steel nut. This is where you will need a socket wrench that fits that nut. The most common size is 1  1/16”. You also may need an extension bar to help loosen it as they can be very tight.

Once loosing off it will unscrew very easy.

Remove fully from the cylinder and discard. Depending on how long and old the anode rod is will determine how long the rod is. I have pulled out old rods that are no bigger than a Bic biro pen hanging onto that big nut.

Step 5- Install the new sacrificial anode- Once the old is removed and put aside grab the new rod.

Using the plumber’s Teflon thread tape go around the thread of the new anode about 16 times. keeping the tape tight as you go around the thread in a clockwise motion like in the picture

Once you have enough plumbers teflon tape around the thread lower the anode rod or flexible anode rod depending which you have back into the top.

If using a flexible rod as you lower it down to each section just straighten it up as you lower it.

It doesn’t have to be perfectly straight for the rod to work.

Make sure when the rod is all the way down just swing it around a bit making sure it’s not fowling on anything inside the tank.

If you are happy screw the rod down into the housing and tighten up firm using the socket from before.

Step 6- Test and commission- Now that we have the new anode rod in turn a hot water tap on inside if you didn’t at step 2 to release the pressure and turn the water on.

What this does is when the water is turned on filling the heater tank with the hot tap on it removes any air in the tank as it fills back up.

Once the tap flows clean with no air mixed with the water turn it off and go check the nut on the anode rod.

Make sure there is no leaks and if all good replace cap if there was one and turn the heating source back on if you turned it off.

That is as easy as it is on How To Replace A Sacrificial Anode rod on a standard hot water tank with a few basic handtools and skill.

Below is a couple different types that are available from amazon through the link