Tankless water heaters have changed the whole process of water heating. Because this kind of water heaters heat the water as your demand to save energy. Its also ensure the constant supply of hot water for laundry, bathing, cooking, and many more.
That’s why tankless water heaters are considered to be the most advanced technology comparing other water heaters in the market. Therefore an efficient and reliable performance, you have to ensure routine maintenance with advanced plumbing tools.
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How to Troubleshoot Tankless Water Heater Problems
Tankless water heating systems are today considered as ‘smart’ since one can easily monitor, control adjusts its operation, efficiency, and performance. Most manufacturers are setting up electronic circuit boards that are referred to as PC boards. Also, a computer chip will aid in solving and diagnosing problems that face the tankless water heaters.
The failure or issues that face the water heaters will exist on the inside of the tankless water heater and will be shown on the display that is situated at the front.
Some of the service problems that might face your tankless water heater to prompt external troubleshoot include:
# Improper Venting: Improper venting is considered to be one of the most popular error. Using the standard B-vent in a wrong manner can destroy the heat exchanger within a short period due to the acidic condensation.
Improper venting is also able to cause leakage of the exhaust gas leaks that would otherwise be considered unsafe.
The tankless water heaters are known to use sealed stainless steel vent pipe that has been approved to be used in the Category 111 appliances.
# Gas Supply Problems: Most people are known just to hook up to the available gas line that is a ½-inch diameter. However, strict attention must be paid to the requirements of the gas line section in the installation manual.
You need to ensure that you size for the maximum BTU is perfect. You also need to ensure that you make an order for the right heater for the type of gas you will be using.
# Temperature/ Water Flow Fluctuation Problems: In case there is a low flow coming from the heater, then first you need to check the input filter. Switch off the cold supply, slightly relieve the hot pressure and remove the filter to check for the debris. You can either clean or replace the filter and check for the flow again.
In case there are variations in temperature or there is inadequate hot water, check the plumbing ‘crossflow’ that will mean there is a connection between the cold and hot water.
However, this might be as inconspicuous as the worn seal in a single-handle faucet. To be able to check for that, you need to shut off the cold supply to the tankless heater and open either the pressure relief valve or the hot water faucet. In case there is a steady flow of water from the hot output after the pipe has been drained, there is always a crossflow at someplace in the plumbing that you will have to fix.
Some of the other temperature fluctuation causes can be the gas line though it might be too small or at times, the temperature of the tankless heater might be set too high with the aim of getting more hot water. It can make the shower to be turned too far to the cold side where it will not allow enough flow of the hot water to keep the water heater steadily.
# Hard Water Problems: In regions where the water is hard with high calcium and magnesium levels, it is appropriate to ensure the water is first heated to make it softer.
However, never use reverse osmosis since it will destroy the heat exchanger. Keeping or removing the minerals in suspension will help lengthen the water heater life and reduce service problems.
# Environmental Issues: It is appropriate to ensure the tankless water heaters are installed in a relatively clean area that can easily be accessed and where is easy access to sufficient combustion air that does not contain any dust particles or chemicals. If any of the conditions are available, a direct vent kit or model should be installed. These explain why beauty salon, restaurants, and industrial applications should get a direct vent unit that will be able to draw combustion air from outside.
Things to Maintain a Tankless Water Heater
To get most out from your tankless water heater, it is important to ensure routine maintenance on your water heater from time to time.
You need to examine the area around the tankless water heater for any combustible materials such as chemicals or papers. Ensure you clear away any minerals that you will come across. You need to frequently exhaust the air inlet and vent for any door, dust or other types of debris that might have accumulated preventing the free airflow that the device will be in need. You also need to check pipes for leaks.
Check the tankless water heater for anything that seems extraordinary like a smell of gas and unusual sounds.
Flush the Water Heater
- You can connect the garden hose to the tankless water heater drain outlet near the base. Put the other end of the garden hose near the floor drain or in a larger basket.
- After that, flush the sediment from the water heater bottom by opening the drain spigot and ensuring the water flows until it is clear.
Adjust the Water Temperature
- In case you have a gas water heater, you can easily adjust the temperature using the thermostat that is situated on the tank.
- If you are using an electric water heater, you need to shut off the power to the unit by flipping the breaker at the service panel.
- Ensure you pull back any installation to expose the thermostat
- You can use a screwdriver to change the temperature of the thermostat in 10 degrees increments
- First, close the panel, turn on the power and then check the water temperature after one hour
If necessary, adjust again. Just feel free to contact us if you need assistance. We will try to get back to you as soon as possible.
Still unsure about your tankless water heater problems and troubleshoot? Tried everything but nothing seems to fix the problem?
Don’t worry! Without a doubt, tankless water heaters are usually low maintenance and highly efficient; however, problems can still occur! If you think that you cannot detect and correct the issues, contact us and save your precious time and let us do the hard work!

Hi, This is Luis. Author at “TheHeatersGuide”. I am a graduate in Mechanical Engineering. Currently researching on heating technology. However, I have learned many home heating techniques and still learning the home heating technolgy. And I love to share my research and reviews.