Why Does a Water Heater Need Flushing?

September 21, 2017

A water heater needs to be flushed periodically to avoid:

  1. A premature breakdown
  2. Hot water shortage problems
  3. Noise from the water heater

We’ll explain how water heater flushing prevents these 3 problems. But first, let’s take a quick look at what “flushing” a water heater really means.

Need your water heater flushed? Just contact us and we’ll get the job done right—right away.

So what exactly is a water heater “flush” in the first place?

A water heater flush is when a professional drains your water heater tank of all its water. Sounds pointless, sure, but the real point behind draining the water is to flush out all of the sediment that accumulates at the bottom of the tank.

So what is this sediment and where is it coming from?

Well that sediment actually comes from your water. You see, many areas in Colorado have “hard water” (water high in minerals like calcium and magnesium). And over time, those minerals settle to the bottom of your water heater, creating “sediment buildup”.

Now, a small amount of sediment buildup isn’t necessarily harmful. But over the years, if your water heater doesn’t get flushed, that sediment can cause your tank to burst (among other costly problems).

So how often do I need to flush my water heater?

Well, it all depends on how hard your water is.

Follow these steps to see how often you should have your water heater flushed:  

Step 1: Find your geographical area on this USGS (United States Geological Survey) map.


Step 2: Determine how hard your water is (determined by the colors red, white, blue and purple)

Step 3: Have your water heater flushed:

  • Once a year if you live in a purple or blue area
  • At least twice a year if you live in a white or red area

3 problems you’ll avoid with a water heater flush

1. A premature breakdown

As sediment starts to build up on the inside of your tank, it insulates the water from the burners. This forces your water heater to eventually overheat the water. And as water heats, it expands. So the hotter the water gets, the more pressure builds up inside the tank—until it bursts a leak, or worse, explodes.

And the worst part? Before your water heater dies, you’ll likely see frequent, expensive repairs due to sediment buildup. For example, if sediment collects on your water heater’s heating element, it can cause it to overheat and require replacement.

2. Hot water shortage

This problem is pretty simple: if you have a 30-gallon water heater with 10 gallons of sediment, you now have a 20-gallon water heater. Which is a drastic difference in hot water supply, especially if you have several people in your household.

3. Noise from water heater.

If a water heater has a good amount of sediment build up inside the tank, it will start making loud popping or knocking noises. That popping noises is caused by overheated water/steam that jostles the sediment at the bottom of the tank as it tries to rise.

Need your water heater flushed? Ask a Denver plumber

Want to avoid all these hot water problems? Make sure you have your water heater professionally flushed on a regular basis.

If you think you’re due for a water heater flushing, just contact us. We’ll send over a reliable plumber who can get the job done quickly and correctly.

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