Navien Tankless Water Heater Problems By Consumer Reports

Navien Tankless Water Heater Problems By Consumer Reports

Many people have been singing about how good tankless water heaters made by Navien are. This is because of the series of benefits these technologically advanced water heaters offer, which cannot get from other brands of tankless water heaters. You know, with Navien tankless water heater, life is pretty much easier because you would have lower bills to pay and a smaller carbon footprint.

Through the use of condensing technology, you will get on-demand hot water, thereby reducing your water bills. With Navien tankless water heaters, you would have a durable, long-lasting water heater that is highly compatible with your existing water system, allowing you to save as much as you want.

As they say, every good thing has its downsides. Irrespective of how effective, excellent, and beneficial Navien tankless water heaters are, they also have their disadvantages. Due to the fact that Navien tankless water heaters are the first to be run on condensing technology, there are bound to be some common issues associated with this new heating system.

Some of those common issues are:

1. Control Board Failures

The control board is one of the crucial parts of a tankless water heater. Most people do not see the reason why this part of the water heater should fail, but yes, it does fail. Also known as “control valve” or “control motherboard,” it does a lot in making your water system work correctly, efficiently, and safely.

Control board failures can be just mild or sometimes serious. One of the symptoms of a control board failure is if your unit completely fails to turn on, or turns on and off repeatedly. As said earlier, the issue might actually be a mild one that would require you to unplug and plug in the power cycling the unit simply.

In some other cases, you might just need to change the control board. For any model of Navien tankless water heater you are using, you can always get a control motherboard replacement. To purchase the right one, just cross-reference your model with the part number on the replacement control board.

It is crucial that you take care of the control board the same way you take care of the whole unit. Keep this part of the unit clean always by ensuring no debris or particles are obstructing the valve. Clean the valve gently with a soft damp cloth and avoid putting materials that are capable of igniting and burning close to it.

2. Navien Flow Sensor Problems

Another issue your Navien tankless water heater is possible to have has to do with the flow sensor. Tankless water heaters provide hot water only when it is demanded for. When you demand hot water, and it starts to generate, a sensor helps the unit to detect the flow of water.

Navien flow sensors also do develop faults and hinder the efficiency of this unit. The flow sensor would, at a point, get rusty. The buildup would disturb operation and shut the unit down. This issue is very rampant among the early models of tankless water heaters made by Navien.

To solve this issue, you can replace the unit’s flow sensor to a Stainless Steel one that will not corrode. You can, however, fix this problem without having to purchase a flow sensor replacement. All you need to do is to install a 5-micron filter in the water inlet. This filter will collect the debris and prevent it from impairing operation.

3. Navien Heat Exchanger Issue

The heat exchanger is another significant part of the Navien tankless water heater. This device passes heat from the water heater gas to the flowing water, thereby heating it. In other words, the heat exchanger is responsible for transferring the heat from the power source to the fluid.

This part of the Navien tankless water heater does not develop issues as frequently as the control valve and flow sensor. But then, there is a possibility of the heat exchanger getting cracked. When this happens, your unit will fail to heat effectively. Also, exhaust gas begins to find its way into your home.


Some parts of the Navien tankless water heaters suffer wear and tear. When a part wears, find a replacement for it to enjoy the continuous effectiveness of the unit.