hot-water-heater-sediment-pic1Hot water heater sediment can be a problem for more than one reason. Sediment inside of your tank will reduce the amount of hot water you have. It will also cost you more to heat your water, since you are heating sediment also.

Not sure if you have a problem with sediment? See the articles, 'Gas Water Heater Troubleshooting' and 'Electric Water Heater Troubleshooting' for a complete listing of all the water heater topics.

Causes of Sediment

Water has minerals and suspended particles in it. When water is still, the minerals and particles will settle out and gravity will cause them to fall to the bottom of whatever is containing the water.

Your hot water tank is a superb example. It is filled with water and for long periods of time it sits idle.

While it is setting still, various minerals will settle to the bottom of your tank. In time this sediment can harden and become a problem.

Problems With Sediment

How much of a problem? Well, have you heard the term 'sedimentary rock'? You get the idea, your water heater can get filled up with a hardened mass of material at the bottom.

There are differing opinions on whether this is harmful or not. Some contend that minerals in water are good for you and that there is no danger in drinking water that contains them. Others contend that the concentration of minerals or other undesirable chemicals is bad for you. That is why you will often read that you should not drink water that comes from your hot water tank.

We are not discussing the safety or dangers of hot water heater sediment. Instead, we are discussing whether or not it has 'unfavorable' or 'troublesome' effects on you water heater. Put simply, hot water heater sediment, can cause problems.

Sediment Issues

Below, we have listed a few hot water heater sediment problems. The severity of these issues will depend on the age of the water heater and the level of build up.


Hot water displacement would be the first thing that comes to mind. Do you have a 40 gallon hot water tank? The equivalent of ten gallons of sediment will mean 25% less hot water. How many teenagers do you have? It is clear that sediment will lower the efficiency of the hot water tank.

Lowered Efficiency

Hot water heater sediment will also affect the heating of the water. Gas hot water tanks heat the water via a flame at the bottom of the tank. What happens when the bottom of the tank is filled with sediment? You have to heat the sediment first. We mentioned minerals. Some minerals do not like being heated all that much. The sediment may react or make noises when heated.

The other issue is that you have to heat the sediment first. Wasn't the goal to heat the water? Do the math, how much does it cost to heat a big pile of sediment, every time you need hot water. If you are here reading an article on this website, I have to believe you are somewhat concerned about cost. Why waste money?

Damage to Heating Elements

Hot water heater sediment is more of a problem on electric hot water heaters. Electric water heaters have an element near the bottom of the water tank. When the sediment builds up high enough, it will burn out the lower element. When the lower element fails you will have a lot less hot water. Not to mention the cost to replace the element.

I don't have the time or inclination to argue or debate this subject. Let's just both agree that eliminating hot water heater sediment is in your best interest.

Removing Sediment

Removing hot water heater sediment can be a periodic maintenance task. As discussed in the previous article, 'Water Heater Sediment Problems', getting rid of sediment can save money and prevent damage.

Is your hot water tank fairly new? I mean a few years old. Flushing the tank out periodically will take care of the problem. Do you have very hard water? You will need to do it more often. I have heard of horror stories where sediment can burn out a lower heating element in as little as six months.


Flushing the sediment out of your hot water tank on a regular basis will be the solution. For instructions, go to 'Flushing a Hot Water Tank' for directions on what to do. It is not that big of a job and doing it regularly will prolong the life of your hot water tank. Even better, it will save you money.

Old hot water tanks with serious sediment build up could be a big job. Hot water tanks do not have that many openings. Electric ones have a few extra ways to get in.

Build up of this kind is due to a lack of maintenance over a long period of time. You can find other articles online that will help you with this problem. Breaking up deeply entrenched and hardened sediment can be a big jog. Replacing the hot water heater at this point might be the course of wisdom. Your water heater probably has other issues, if it is this old.