How Your Water Heater Affects Your Home's Water Quality

Residential hot water has turned from a luxury into a modern necessity over the past century. The water heater in your home allows you to thoroughly and efficiently bathe, wash various items, and even prepare food. However, the appliance tasked with heating your home's water has a significant effect on your water quality. Here's how your water heater will positively or negatively impact the quality of your hot water.

The Root Of The Problem: Minerals

Although you may not want to believe it, your residential water supply isn't completely pure. Even though the majority of the contaminants found in your municipal water supply are trapped and eliminated by a complex filtration system, calcium, lime, and magnesium will manage to find their way into your plumbing system.

Minerals are problematic for several reasons. Aside from causing corrosion damage to your various pipelines, they'll also reduce the quality of your water when they're heated.

For example, calcium releases calcium sulfate when it's heated. Calcium sulfate is an odorless and colorless substance that will irritate your eyes, skin, and even your respiratory system since it's hygroscopic (has the ability to absorb moisture from air). If you frequently experience dry, itchy skin after bathing, then chances are your water supply contains a large amount of calcium sulfate.

Dry skin isn't the only issue caused by calcium sulfate. Additionally, a high volume of calcium sulfate inside your water tank will hasten corrosion damage and decrease the lifespan of your anode rod.


Since minerals are capable of drastically reducing the lifespan of the metal parts inside your water heater, manufacturers design their tanks with an anode rod. The anode rod in your water heater is made from a noble metal that will attract corrosive minerals and neutralize them before they can damage the rest of your tank.

However, your anode rod won't last forever. The lifespan of your anode rod will be determined by the mineral content of your water, the amount of water you use on a daily basis, and the volume of your tank.

Additionally, the use of a water softener will further reduce the lifespan of your anode rod. The average anode rod lasts about five years, but if these factors are affecting your anode, you'll need to replace it at a much shorter interval.

If your anode rod completely deteriorates, then the minerals that once attacked your anode will begin corroding your dip tube, tank lining, or even your heating elements—if you have an electric heater. Once corrosion begins to occur inside your tank, your water quality will be drastically reduced. Flakes of rust, metal, and large amounts of minerals will be visible in your water supply.

Luckily, you can inspect your anode rod to determine when it requires replacement. Simply unscrew the bolt (anode rods always have 1-1/16th-inch bolts) on the lid of your tank and pull it upwards. If your rod is covered in calcium, pitted to its core, or even broken in half, then it needs to be replaced immediately. If these issues aren't present, then reinstall your anode and check it again in a couple months.

Debris Accumulation

The neutralized minerals and sediment in your water supply will settle at the bottom of your tank. Since nearly all water heaters have a straight dip tube, these debris particles will immediately rest at the bottom of your tank.

Although this issue may not sound like a problem, it is—as the debris is heated, it turns into scale. As the scale is heated, pockets of air will blast it loose and send it through your plumbing system. Once scale has formed inside your tank, it's extremely difficult to remove without the use of chemicals that will further affect your water quality.

If you've identified a recent drop in your home's water quality, or if you want to maintain the integrity of your water, then make sure your water heater is always kept in good condition. If you aren't able to keep minerals from causing these three problems, then hire a professional plumber who specializes in water heaters to service yours for you.