A water heater tank is an insulated container that holds hot water until it’s needed. Tank-type water heaters use either gas or electricity to heat the water and have a thermostat to control temperature. More by clicking here.

Sacrificial anode rod

A metal rod screwed into the top of a tank-style water heater, this component is positioned to attract and rust away corrosive minerals that would otherwise eat through your hot water tank. Sacrificial anode rods are usually made of magnesium, aluminum, or zinc; each type serves a different purpose depending on your home’s water quality. Magnesium anode rods are the most popular because they protect tanks best in soft water. However, they corrode quickly and can cause a rotten egg smell in the hot water. Aluminum rods are cheaper than magnesium but decompose more quickly, requiring regular replacement. Zinc anode rods combat bacteria that can create odors in hot water.

While the sacrificial anode rod ultimately sacrifices itself for the benefit of the steel tank, it should be replaced at least every two years. Loud noises and popping sounds during heating are common indicators of a fully corroded anode rod. Water quality can also affect anode rod longevity; hard water leads to enhanced mineral build-up, and homes with a sodium-based water softener may see their anode rods corrode more rapidly due to trace amounts of salt.


A water heater tank has a dial or thermostat that controls the temperature of the water inside it. It is recommended to set it to 120-140 degrees Fahrenheit to ensure you always have enough hot water for household needs. It is important to estimate your peak hour usage when calculating how hot you need your water to be.

Before you can start working on your water heater tank, it is a good idea to shut off the power by turning off the switch at the electrical panel. You will then need to remove the access panel and insulation and detach the cover from the reset button. Once you have done this, you can use a digital multimeter to test for continuity in the thermostat and element terminals. The meter display should show close to zero Ohms of resistance if there is electrical continuity between them. If it does not, then it is likely that one of the components has failed.

Dip tube

The dip tube directs incoming cold replacement water into the bottom of the tank where it is heated. When the dip tube deteriorates, cold water mixes with hot water on top of the tank, reducing the overall water temperature. This can cause your home’s faucets to deliver lukewarm water rather than hot.

A new tube is easy to install. Shut off the power and close the drain valve (for an electric water heater) or gas dial (for a gas water heater). Use a flat screwdriver to loosen the inlet port nipple on the old tube, then pull it out. Insert the new tube into the inlet port, making sure it reaches all the way to the bottom of the tank.

Before restoring power or turning on the gas, test the new dip tube by putting a hose to the tank drain valve and running water through it. If the water leaves the hose quickly and cools, the dip tube is working properly.

Pressure relief valve

The water expands as it heats, creating high pressure within the tank. If this pressure gets too much, the temperature and pressure relief valve activates to release steam and hot water through an auxiliary discharge tube. This prevents the water heater from exploding and protects the home from possible damage.

The valve is usually welded to the top of the tank or very high up on one of its sides and is connected to a long discharge tube that points downward from the valve. It’s important to test the valve regularly for mineral build-up, which can cause it to become stuck or not open when necessary.

To test your valve, start by positioning a bucket underneath the discharge tube. Carefully lift the valve switch until water starts coming out of the tube and into the bucket. This is a good sign that the valve is working correctly. You should also listen for excessive rattling, which may indicate too much pressure on the valve’s inner walls. Next blog post.