Stiebel Eltron Tankless Water Heater Troubleshooting: Common Problems and Solutions

Stiebel Eltron is a German company that produces high-quality tankless water heaters that are energy-efficient, reliable, and durable. However, like any appliance, they can encounter some problems over time. One of the most frustrating issues is when the tankless water heater stops working or does not heat the water properly.

In this blog post, we will explain how to troubleshoot a Stiebel Eltron tankless water heater and how to fix some common problems. We will also answer some frequently asked questions about this topic.

How to Troubleshoot a Stiebel Eltron Tankless Water Heater

Before you start troubleshooting your Stiebel Eltron tankless water heater, you should always read the manual of your model and follow the safety precautions. If you are not sure what you are doing, you should contact a professional plumber or technician to service your heater.

 Steps you can take to troubleshoot your Stiebel Eltron tankless water heater

Check the power supply

If your tankless water heater is not working at all, the first thing you should check is the power supply. Make sure the unit is plugged in and the switch is on. Then, go to your circuit breaker box or panel and inspect all the circuit breakers connected to your water heater. If any of them are off, turn them on and try to operate the heater again.

Check the error code

If your tankless water heater has a digital display, it may show an error code when there is a problem. The error code can indicate what is wrong with the unit and what needs to be fixed. You can look up the error code in the manual or online and follow the instructions to resolve the issue.

Check the flow rate

If your tankless water heater is not heating the water enough or fluctuating between hot and cold, it may be because the flow rate is too low. The flow rate is measured in gallons per minute (GPM) and indicates how much water the heater can heat at a given time.

If the flow rate is below the minimum activation rate of your model, the heater will not turn on or will turn off intermittently. You can increase the flow rate by opening more faucets or reducing the demand for hot water.

Check the flow sensor

If your tankless water heater is not turning on or turning off randomly, it may be because the flow sensor is clogged or not spinning freely. The flow sensor is a device that detects the water flow and signals the heater to turn on or off.

If the flow sensor is dirty or stuck, it will not work properly and cause problems with the heater. You can clean or replace the flow sensor by following the instructions in the manual.

Check the safety thermal cut-out

If your tankless water heater is not heating the water at all, it may be because the safety thermal cut-out has tripped. The safety thermal cut-out is a device that protects the heater from overheating by cutting off power when the water temperature exceeds a certain limit. You can reset the safety thermal cut-out by pressing the reset button on the unit or on the remote control.

Check the water quality

If your tankless water heater is not heating the water properly or causing corrosion or scale buildup, it may be because the water quality is poor. You can test the water quality by using a water test kit or by sending a sample to a laboratory. You can also install a water filter or a water softener to improve the water quality and prevent damage to your heater.

Check the venting system

If your gas tankless water heater is not working or making noises, it may be because the venting system is faulty. The venting system is responsible for removing the exhaust gases from the combustion process.

If the venting system is not installed properly or is damaged, it can cause backdrafting, condensation, carbon monoxide poisoning, or fire hazards.

You can check the venting system by inspecting the vent pipe for any cracks, holes, blockages, or leaks. You can also use a carbon monoxide detector to monitor the air quality around the heater.

Frequently Asked Questions (FAQs)

Here are some common questions and answers about Stiebel Eltron tankless water heater troubleshooting:

How do I reset my Stiebel Eltron tankless water heater?

To reset your Stiebel Eltron tankless water heater, you can follow these steps:

• Turn off the power supply to the unit by switching off the circuit breaker or unplugging the cord.
• Wait for a few minutes for the unit to cool down.
• Press and hold the reset button on the unit or on the remote control for 10 seconds.
• Turn on the power supply to the unit by switching on the circuit breaker or plugging in the cord.
• Check if the unit is working properly and if there are any error codes displayed¹.

How do I descale my Stiebel Eltron tankless water heater?

To descale your Stiebel Eltron tankless water heater, you can follow these steps:

• Turn off the power supply and the water supply to the unit.
• Disconnect the inlet and outlet pipes from the unit and attach them to a pump and a bucket.
• Fill the bucket with a descaling solution made of white vinegar and water (1:4 ratio) or a commercial descaler.
• Turn on the pump and circulate the solution through the unit for about an hour or until there are no more bubbles or foam.
• Drain and flush the unit with clean water until there is no more vinegar smell or residue.
• Reconnect the inlet and outlet pipes to the unit and turn on the power supply and