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What To Do When Your Tankless Water Heater Is Not Heating

Published on September 29, 2023
Written by kristinia

Has your tankless water heater left you cold and frustrated? Nothing can beat the disappointment of expecting a warm shower and getting hit with cold, freezing water instead.

But don’t fret: there’s an excellent reason why your tankless water heater may not be heating the water properly.

At Full Speed Plumbing of Mount Vernon, WA, we know all there is to know about restoring comfort to your showers. Follow along as we examine some of the common causes behind tankless water heater failure, as well as potential solutions.

If your task seems overwhelming, don’t despair! Our professional and efficient service is only a phone call away!

6 Reasons Why Your Tankless Water Heater is Not Heating Properly

Here are six of the most common reasons why tankless water heaters refuse to heat up properly:

  1. Sediment Build-Up: Over time, tankless water heaters may accumulate mineral and sediment deposits from their water supply that interfere with heat transfer, preventing it from reaching the desired temperature. Regular flushing and cleaning can help address this issue.
  2. Faulty Heating Elements: One of the leading causes of lack of hot water is worn-out or damaged heating elements that cannot effectively heat water, leading to its inaccessibility. In such an instance, replacing them may be your only recourse to restore the hot water supply.
  3. Size Mismatch: If the tankless water heater you own is too small to meet the demands of your household, it could struggle to deliver sufficient hot water. One possible solution may be upgrading to one capable of handling higher volumes.
  4. Outdated Unit: Like any appliance, tankless water heaters have a finite lifespan. If yours has been operating for an extended period, it could be time for an upgrade.
  5. Improper Installation: Tankless water heaters must be properly installed for maximum effectiveness. If you are experiencing persistent issues with your heater, it may be worth exploring whether it was installed correctly.
  6. Gas Supply Issues: If your gas-powered tankless water heater is failing to produce hot water, it could be caused by issues with its gas supply – this may include low pressure or even a gas leak – so in such instances, professional assistance should be sought immediately.

Remember, addressing these issues can sometimes be complex and potentially dangerous, especially when dealing with gas supply or electrical issues. When in doubt, it’s always best to reach out to a professional for safe and effective repairs.

Addressing the Problem: Dealing With a Tankless Water Heater That’s Not Hot Enough

If you are up for a challenge, here is a general guide that should help address common problems associated with tankless water heaters.

Step 1: Preliminary Checks

To start with, it is essential that the power supply and gas (if applicable) are both functioning normally. In addition, make sure that water has been turned on – sometimes this could be enough of a solution!

Step 2: Check for Sediment Build-up

Remember to inspect the unit for any signs of sediment build-up by opening it up. Consult the owner’s manual or a professional plumber before beginning this step. If any build-up is found, flushing and cleaning must occur before further operation of your unit. 

Step 3: Assess Heating Elements

If your heating elements are easily accessible, carefully examine them for any signs of wear or damage. If they appear damaged, a replacement will likely be necessary.

Step 4: Assess Your Unit

Evaluate whether your current water heater can keep up with your household’s hot water demands. If it frequently runs out of hot water, upgrading to a larger model might be in order. 

Step 5: Evaluate Its Age

Depending on its age and issues, replacing it could be more cost-effective in the long run than continuing to use an old tankless water heater. 

Step 6: Verify Installation

Make sure that your tankless water heater has been correctly installed. If unsure, consulting a professional may be wise.

If you’ve taken these steps and you’re still left shivering in the cold, it might be time to call in the professionals. At Full Speed Plumbing, we’re always ready to help. Don’t hesitate to give us a call. We’ll get your heater back up and running, and the hot water flowing again in no time!

What To Do When Your Tankless Water Heater is Not Heating — Conclusion

Overall, there may be numerous reasons for your tankless water heater not providing you with the warmth you’d expect, from sediment build-up and broken heating elements to improper installation or outdated units. While you might be able to take steps yourself in troubleshooting these issues yourself, professional help is always recommended as safety should always come first.

At Full Speed Plumbing, our priority is you – not our tankless water heater! So if your showers have become frigid and you require assistance with it, don’t hesitate to contact us when you’re ready – let’s bring warmth back into your home together.

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17675 Washington 536
Mount Vernon, WA 98273
Full Speed Plumbing

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