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Tankless Water Heater Maintenance

Tankless Water Heaters

Tankless Water Heater Maintenance: Ensuring Optimal Performance

When it comes to hot water systems, tankless water heaters have gained popularity for their energy efficiency and on-demand hot water supply. These compact and reliable devices require proper maintenance to ensure their longevity and optimal performance. In this article, we will explore the essential maintenance tasks that can keep your tankless water heater running smoothly and provide you with uninterrupted hot water. By following these maintenance guidelines, you can avoid potential issues and extend the lifespan of your tankless water heater.


Understanding Tankless Water Heaters

Tankless water heaters, also known as on-demand water heaters, provide hot water instantaneously without the need for a storage tank. These units heat water directly as it flows through the device, saving energy and eliminating the standby heat loss associated with traditional tank water heaters.

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$600 Federal Tax Credit on Tankless Water Heaters!

Beginning 2023, the expanded version of 25C, now called the Energy Efficient Home Improvement Tax Credit (under the Inflation Reduction Act of 2022), provides a maximum credit of $1,200 annually for most taxpayers. It is $600 for any single energy property item (including Tankless Water Heaters and Boilers)…Learn More

Why Tankless Water Heater Maintenance is Important

Proper maintenance is crucial for tankless water heaters to ensure their optimal performance and prevent potential problems. Neglecting maintenance tasks can lead to reduced efficiency, diminished hot water output, and even system failure. Regular maintenance helps to remove mineral deposits, improve energy efficiency, extend the lifespan of the unit, and maintain consistent hot water supply.

Regular Cleaning and Descaling

One of the primary maintenance tasks for tankless water heaters is regular cleaning and descaling. Over time, mineral deposits can accumulate on the heat exchanger, affecting its performance and efficiency. Follow the manufacturer’s instructions to safely clean and descale the unit using a descaling solution or vinegar. Regular cleaning helps prevent clogs, maintain heat transfer efficiency, and prolong the life of the water heater.

Checking and Flushing the Heat Exchanger

The heat exchanger is a vital component of a tankless water heater. It transfers heat from the burner to the water flowing through the unit. Over time, sediment and debris can accumulate in the heat exchanger, reducing its effectiveness. Regularly inspect and flush the heat exchanger to remove any build-up and ensure optimal heat transfer.

Inspecting the Burner and Ignition System

The burner and ignition system of a tankless water heater should be inspected for any signs of damage or malfunction. Ensure that the burner is clean and free from debris. Check the ignition system for proper operation and ensure that the flame is stable and blue. If you notice any issues, consult the manufacturer’s manual or contact a professional for assistance.

Monitoring Water Pressure

Maintaining proper water pressure is essential for the optimal performance of a tankless water heater. High water pressure can strain the unit, leading to premature wear and potential leaks. Use a pressure gauge to monitor the water pressure regularly and adjust it within the recommended range specified by the manufacturer.

Cleaning or Replacing Air Filters

Tankless water heaters have air filters that prevent dust and debris from entering the unit. Clogged air filters can obstruct airflow, affecting the combustion process and reducing efficiency.

To ensure optimal performance, it’s important to clean or replace the air filters regularly. Consult the manufacturer’s instructions to locate the air filters and follow the recommended cleaning or replacement schedule. By keeping the air filters clean, you can maintain proper airflow and enhance the efficiency of your tankless water heater.

Checking for Gas Leaks

If you have a gas-powered tankless water heater, it’s crucial to check for gas leaks as part of your maintenance routine. Inspect the gas connections and fittings for any signs of leaks, such as a noticeable odor or hissing sound. If you suspect a gas leak, turn off the gas supply immediately and contact a qualified professional to address the issue.

Verifying Proper Ventilation

Proper ventilation is essential for the safe operation of a tankless water heater. Check the venting system for any blockages, such as debris or bird nests, that could impede the exhaust gases from properly venting outside. Ensure that the vent pipes are securely connected and free from damage. If you notice any ventilation issues, contact a professional to assess and address the problem.

Testing Temperature and Pressure Relief Valve

The temperature and pressure relief valve (TPR valve) is a crucial safety feature of a tankless water heater. It releases excess pressure or temperature to prevent the tankless unit from exploding. Regularly test the TPR valve by lifting the lever to ensure proper functioning. If the valve does not release water or shows signs of leakage, it may need to be replaced. Consult the manufacturer’s instructions for guidance.

Insulating Hot Water Pipes

Insulating the hot water pipes connected to your tankless water heater offers several benefits. It helps reduce heat loss during water transfer, ensuring hot water arrives at the faucets quickly and efficiently. Insulation also helps conserve energy and can prevent condensation on cold pipes in humid environments. Wrap the hot water pipes with pipe insulation to enhance efficiency and minimize heat loss.

Preventing Freeze Damage

If you live in a cold climate, protecting your tankless water heater from freeze damage is crucial. Insulate the unit and any exposed piping to prevent freezing during frigid temperatures. Additionally, consider installing freeze protection devices or adding a dedicated freeze protection system to safeguard your tankless water heater from extreme cold conditions.

Troubleshooting Common Issues

Despite regular maintenance, you may encounter common issues with your tankless water heater. Some common problems include insufficient hot water, fluctuating temperatures, error codes, or ignition failures. Consult the manufacturer’s manual for troubleshooting guidance or contact a professional for assistance if you are unsure how to address the issue.

Hiring a Professional for Maintenance

While many maintenance tasks can be performed by homeowners, it’s advisable to schedule periodic professional maintenance for your tankless water heater. A qualified technician can perform a comprehensive inspection, conduct necessary maintenance procedures, and ensure your unit operates optimally. Professional maintenance can identify potential problems early on and help extend the lifespan of your tankless water heater.


Proper maintenance is essential for maximizing the performance and lifespan of your tankless water heater. By following the outlined maintenance tasks, such as regular cleaning, inspecting components, monitoring water pressure, and addressing potential issues, you can ensure your tankless water heater continues to provide reliable hot water efficiently. Remember to consult the manufacturer’s instructions and, when in doubt, seek professional assistance to guarantee the safe and effective operation of your tankless water heater.

Everything You Could Ever Want to Know About Tankless Water Heater Maintenance

Frequently Asked Questions

It’s recommended to clean your tankless water heater at least once a year or as per the manufacturer’s instructions. However, if you have hard water with high mineral content, more frequent cleaning may be necessary.

Many maintenance tasks can be done by homeowners, such as cleaning the unit, checking for gas leaks, and monitoring water pressure. However, it’s advisable to schedule professional maintenance periodically to ensure comprehensive inspections and address any potential issues effectively.

If your tankless water heater is not providing sufficient hot water, there could be several reasons. First, check for any error codes or indicators on the unit. Ensure that the water flow is adequate, and there are no obstructions in the pipes. Additionally, consider checking the burner, heat exchanger, and TPR valve for any issues. If the problem persists, it’s recommended to consult a professional for further assistance.

With proper maintenance and care, tankless water heaters can last for 15 to 20 years or even longer. Regular maintenance, including cleaning, flushing, and inspections, helps ensure the longevity and optimal performance of the unit.

While some homeowners may have the necessary skills and knowledge to install a tankless water heater, it’s generally recommended to hire a professional for installation. Proper installation is crucial to ensure safety, proper venting, and efficient operation of the unit. Professional installers have the expertise to handle gas, electrical, and plumbing connections correctly.

Yes, even if you have soft water, it’s still important to flush your tankless water heater regularly. While soft water contains fewer minerals, sediment and debris can still accumulate over time, affecting the unit’s performance. Flushing helps remove any build-up and maintain optimal efficiency.

It’s best to consult the manufacturer’s instructions for recommended descaling solutions. Different manufacturers may have specific recommendations or requirements. Using the appropriate descaling solution ensures effective cleaning without damaging the internal components of your tankless water heater.

To prevent limescale build-up, you can install a water softener or a whole-house water filtration system. These systems remove minerals from the water supply, reducing the chances of mineral deposits forming in your tankless water heater. Additionally, regular cleaning and descaling will help keep limescale at bay.


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