Hot Water Runs Out Quickly? Two Possible Water Heater Issues

No one likes a cold shower, but that’s exactly what you’re getting after a few minutes.

So what’s the deal?

Well, let’s get the obvious out of the way:

  • Has your family grown? If so, you may just need a larger tank.
  • Are you running too many hot water appliances at the same time? If so, stop.
  • Is your water heater’s temperature setting set below 120 degrees? If so, turn it up to between 120 to 140 degrees.

If those aren’t the issue, there are two possibilities that will cause you to quickly run out of hot water:

  • Broken dip tube
  • Sediment build-up in the tank

Broken dip tube

This may be the problem if

Your problem started only recently, and you’ve found small bits of plastic in the:

  • Shower head
  • Clogging strainers
  • Appliance filter screens

What this problem is

The dip tube is in the water heater tank and shoots cold water to the bottom of the tank where the heating of the water occurs. If it’s broken, cold water fills the top of the heater and begins to flow right out of the hot side. The water never gets the chance to heat. You can see where the dip tube is located in this diagram.

What to do about it

Call a professional to replace the dip tube.

However, repairing the water heater may not be worth it if it’s 10+ years old—the typical lifespan of a tank water heater. (Source: National Association of Home Builders.)

If you’re thinking about replacing the water heater, read our article, Water Heater Buyers’ Guide – Tankless or Traditional?

Sediment build-up in the tank

This may be the problem if

you’re problem has been more gradual, and your water heater has not been flushed every year.

What this problem is

Sediment is loose minerals that have settled to the bottom of the water heater tank. Sediment comes from minerals and deposits naturally in our water supply. It includes sand, silt, rust, etc.

Sediment causes you to quickly run out of hot water for 2 reasons:

  • Takes up space in the tank, leaving less room for hot water
  • Insulates the water in the tank from the heating source at the bottom of the tank. Imagine trying to boil a tea kettle on your stove placed on top of bricks. The burner will need to heat the bricks first before the heat can transfer to the tea kettle.

What to do about it

Get the water heater drained and flushed to get rid of all the sediment. You can either DIY.

Learn more about the importance of water heater flushing in our article, “Should I Flush My Water Heater?” [FAQ]

Get your water heater repaired and keep it working in tip-top shape

Mr. Plumber can not only get your water heater back in working order, but we can keep it that way with a plumbing maintenance plan.

Contact us with your questions.

Mr. Plumber has been serving the plumbing needs of homeowners in the greater Atlanta metro area since 1966.

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