Tankless Water Heater Shut Off During Shower

Before going to sleep, you are taking a hot shower, singing songs, all in the right place, and suddenly you are not singing songs along with a shivering body because of icy water! So, what happened? It’s a matter of surprise. You may ask why! Well, it is because your tankless water heater shut off during the shower unexpectedly

Tankless water heater holds many benefits to give. For instance, their size takes up less space as they directly heat the water. They consume less energy, which causes a family to save money depending on the usage. A tankless water heater can supply 1-5 gallons per minute based on the unit. Therefore, whenever you are choosing a tankless water heater, consider the unit with importance.

Besides the advantages, there are also some drawbacks, such as abruptly shutting off during the shower. However, to avoid the drawbacks, some things need attention.

The Tankless Water Heater Shut Off During Shower Behind The Reason

Here we are discussing some reasons about your tankless water heater suddenly shut off during a shower given below:

Underpowered Unit

At first, it should be installed and maintained correctly. When it is ensured, and still it gets off during a shower, that means the unit you are using can’t supply enough hot water in a minute if you are attempting to do so many works simultaneously such as laundry, dishwasher, shower, etc. Then it is most likely the case where you overrated the capabilities of your on-demand hot water system.

Tankless Water Heater Shut Off During Shower

When you are switching to tankless water heaters, take the decision wisely. At the time, you may think that purchasing an underpowered unit and upgrading it slowly will be the best idea. Yes, initially, it sounds good, but surprisingly, it’s the worst idea you ever have.

As tankless water heaters will help you save money in the long run, invest in a unit with good power. Moreover, you can use some tankless water heater rather than just one if your family size demands it. However, the obstacle can be faulty plumbing, electric power, and gas also.

Flushing Routinely

Another reason can be flushing routinely because it needs to clear the mineral deposit layer that grows inside the heat exchanger. In routine maintenance, it is critical because water heaters cannot function well when these mineral deposits are creating a barrier.

Moreover, the consequence is that the tankless water heater shuts off unexpectedly. Thus, flushing is essential for extending the tankless water heater’s life and for avoiding unwanted issues.

Improper Installation

One more reason can be when the installation of a tankless water heater is not perfect. Sometimes it takes time to show up the mistakes. But if it’s not installed correctly, then problems will come for sure.

Problems Regarding Gas Supply

Another reason can be gas supply problems. It will turn off if it isn’t getting enough fuel. If the heater is not getting the gas that it needs, then there might be different problems.

Most often, these problems lay on a leak and faulty gas valve. Gas flow is getting limited when there is a defective valve. So tankless water heater stops working. Besides, if it’s a matter of leak, then it is a serious issue that demands professional attention.

Filthy Thermopile Or Pilot Light

One of the crucial reasons can be the dirty parts. A dirty element in the water heater can interrupt its operation, and A bunch of problems is familiar when there is a dirty part. Trouble may have happened in thermopile or pilot light. As a result, the water heater gets off. It might be that they are dirty or broken.

The pilot light can get dirty somehow from soot, dust, and other particles. When it gets dirty, it creates a barrier in the flow of oxygen. One can restart it, but it will experience the same result again.

With pilot light, thermopile gets a signal, and accordingly, gas controls get turn on. Therefore, when there is dirt in the pilot light, the thermopile does not work correctly, and the water heater will not start heating. It might be the problem, so we need to be sincere about that.

Air Inlet Shuts Off

The air inlet provides air to the gas water heater’s main burners. If they don’t get adequate oxygen because of a clogged air inlet, the result will be that they will shut off.  Other dirt problems can also be prevented by maintaining the gas water heater regularly.

There can be other unfamiliar problems that could be the reason for shutting off the water heater. If you can’t diagnose the problem, then you can call a plumber. A plumber can find out the problem for you and explain what’s going on and what can be done to prevent the problem.

Some more things that could be the reason for The tankless water heater shut off during shower. They are:

  • Maybe a loose wire. If this is the issue, then call a plumber as soon as possible.
  • Monitor the heater that it is getting the right amount of electricity, gas, and water. Otherwise, you may face the same scenery again and again.
  • Make sure that there is no debris in it. Thus, regularly check it.
  • A low water flow rate can be a significant problem. Some tankless water heater requires a minimum flow rate, and if it is not matched, then the heater will not work correctly. So, it should be taken care of.
  • If the water heater’s temperature is set too high, it can cause the heater to turn off during a shower. Hence, it should be in consideration.
  • Suppose there is any damage or problem with the flow sensor. It is another essential thing that needs to be in mind.
  • If the venting pipes are too small, it can be a problem.
  • On gas tankless water heater if the installed gas lines are of the wrong size.
  • When propane is used, it experiences an out of propane.
  • If the electrical wire loses, it may happen.
  • While installing heat exchangers improperly and the ignitor damage, this situation can occur.


 A tankless water heater is always useful and popular though the tankless water heater shuts off during the shower. For some reasons mentioned above, sometimes your tankless water heater may stop supplying water. It is irritating, especially during the winter season.

The problems are not so significant and may fix them quickly or get a plumber. It gives more advantages than a water heater with a tank. For example, an instant water supply saves electricity bills or saves space, etc. By maintaining and using the water heater carefully, you may prevent accidental shutting off the water supply.

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