Water heater tanks have 1-2 aluminum or magnesium anode rods that protect any exposed steel from becoming corroded. They are sometimes called sacrificial anode rods or anti-corrosion rods.
If your water heater has a 10+ year guarantee then it will typically have two rods for extra security. If you have soft water in your area/home, then it is best to use magnesium anode rods. However, aluminum anode rods are best if your area/home has hard water.
The main line water conditioning/softening system has a pipe that supplies water to the hot water heater. You should be able to find a shut off valve for the cold water supply on the water heater “supply” side.
The inlet pipe is on top of the water tank and will send cold water to the bottom via the dip tube. This way, the cold water will not cool down the hot water in the tank. The hot water then leaves the water tank through the outlet pipe, which is situated at the top of the tank.
Sometimes, you will see that the outlet and inlet pipes are reversed because this is more convenient. If this is the case, then the dip tube will be moved to the outlet pipe. If it has not been, then this may cause problems.
Relief valves are there to protect the water heaters. They allow the water to escape the heater if the pressure of temperature becomes too high. This safety measure is in place so the tank does not blow up.
You should be able to find the temperature-pressure relief valve at the top or on the side of the tank. If you see it on the top of the tanks, it indicates that you have an older water heater model, and you may want to consider replacing it.
This is because the practice of placing the temperature-pressure relief valve on top of the water heater is no longer considered safe. You should be able to see a discharge tube or metal extension tube down the side of the tank, around 6 inches from the floor.
Generally, hot water heaters have 140 degrees of output water, but you will be able to change these settings via the thermostat. If you want a more energy efficient and safe water temperature. Then anything between 115-120 degrees is typically recommended.
There should be a drain valve at the base of every water heater tank. You should attempt to drain out a few gallons of water multiple times a year to make sure sediment and sludge does not build up in your water heater.