5 Tankless Water Heater Troubleshooting Tips

Sometimes we take for granted the hot water that comes running out of our faucets in just a few seconds, until the flow of hot water breaks.

Here are some tips that might help you prevent and fix some of the most common tankless water heater problems in your home.

Problem #1: Mineral Clogging

Since there are a lot of minerals in the water, such as magnesium, calcium and others, one of the most common issues that most water tankers develop is mineral clogging.

Fortunately, this is an issue that can easily be overcome by using a proper water softener which will enable you to minimize the mineral buildup. It is always a good idea for you to do the cleaning regularly.

The new modern tanks with built-in sensors typically have sensors that automatically detect the build-up and indicate when you need to do the cleaning.

Problem #2: Not Heating Up

Not heating up is one of the most common problems which is usually found in gas tankless water heaters and it occurs because the thermocouple – the safety device that senses when a flame is present – has worn out and needs to be replaced.

If this is the case, you do not need to worry, this part is fairly inexpensive and you can easily replace it yourself. In some cases, the burner may not light because it needs cleaning. This would be a good time to contact a residential plumber to avoid any major issues.


Problem #3: System Overload

Sometimes too much hot water can simply overload the system just like too many tabs may overload your computer. This is usually an easily solvable problem.

When you have multiple faucets running, in an attempt to work harder and provide enough hot water, your system can completely shut down.

To fix this issue, you need to reset the water heater. Give it a few minutes to start running again, and then limit the simultaneous applications to just one at a time.

In most cases this will return your system to normal, however, if the problem persists, consult a professional.

Problem #4: Venting & Combustion Issues

If your tankless water heater is showing an error code that says blocked vents or exhaust, your heater is experiencing a venting or combustion issues.

In order to solve this problem, you need to identify and check all lines to make sure that they are securely connected, in good condition and don’t have any water leaks.

If there is some object blocking the air supply, this issue may appear again. You need to check the intake and exhaust vents both inside and outside your home and make sure that nothing is blocking the venting.

Problem #5: Too Hot or “Flame Failure”

The ideal temperature should be 120-125 degrees. This is the safety temperature recommended for everyone, and you can even lower it further if you have sensitive skin or live with small children.

If you notice that the water is too hot and there is a “flame failure” error code on your tank or if it simply is not firing up properly, most likely the issue is an ignition failure which is related to the gas supply/pressure or gas valve.

If you suspect this issue, do not try to solve this issue on your own, call Super Service Plumbing at (707) 544-6444 today.

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Finding a residential plumbing contractor in California provides the convenience of getting to your bay area home without the added stress or cost of waiting around. Instead, your tankless water heater or backflow can start to receive the necessary plumbing repairs you’re looking for right away. Super Service Plumbing is one of the top plumbing companies on the west coast, located in the heart of wine country in Sonoma County.

Super Service Plumbing provides plumbing services in Santa Rosa and throughout Sonoma County and is always available for emergency plumbing repairs 24/7. So call one of the best plumbing companies near you at (707) 544-6444 today.

Tankless Water Heater FAQs

plumbing faqs

What is the downside of a tankless water heater?

Tankless water heaters can produce an endless supply of hot water for your home. They usually take up less space, are much safer long-term, and have much lower risks of leaking. The most common disadvantage of a tankless water heater is the upfront cost of the installation, as it is significantly higher than installing a traditional hot water heater.

Is a tankless water heater worth it?

Studies show that a tankless water heater is more efficient and uses less energy than a conventional water heater. According to the U.S. Department of Energy, you can expect $25 – $107 in annual savings. And, if you use hot water less frequently (less than 41 gallons a day for example), your tankless water heater can be 24% – 34% more efficient.

How big of a tankless water heater do I need?

For residents in Sonoma County, you’ll want your water heater to be able to heat at least 5.2 gallons of water. This means you should consider purchasing a tankless water heater that can produce at least a 60-degree rise in temperature at 5.2 gallons per minute.

Proud to help our Sonoma County communities including:

Santa Rosa, Petaluma, Rohnert Park, Windsor, Healdsburg, Sonoma, Cloverdale, Sebastopol, Cotati and beyond.

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