When your Junkers boiler starts to malfunction, it can be a frustrating experience trying to figure out what’s wrong. Fortunately, boilers are designed to display specific error codes that help us identify the issue. These codes, though they may seem cryptic at first, are actually a very useful tool for diagnosing and troubleshooting. In this article, we’ll introduce you to the Junkers boiler error code table, explaining how you can use this information to better understand what’s happening with your boiler.
What are error codes?
Error codes are messages that the boiler generates when it detects abnormal operation or an internal problem. Each code is associated with a specific issue, from faults in the electrical system to problems with water pressure. Understanding these codes is the first step towards being able to fix the issue.
How to use the error code table
The error code table we provide below is a valuable tool for any Junkers boiler owner. Here, you’ll find a list of the most common errors, along with their description, the likely cause, and suggested solutions. It’s important to remember that while some solutions may be simple and within your reach, others may require the intervention of a specialized technician.
To use the table, simply look up the error code displayed by your boiler in the “Error” column. Then, read the description to understand the issue, and check the “Solution” section for recommended steps to fix it.
| Error | Description | Cause | Solution |
|---|---|---|---|
| A7 | Hot water temperature probe defective | Verify continuity, possible derivation in the probe and connection cable. | |
| A8 | Communication interrupted. | Check the e-bus cable | |
| C6 | Flue gas extractor fan not working. | Check the fan’s power cable, plug, and the fan itself, replace if necessary. | |
| CC | Presence of external temperature probe not detected. | Check the condition of the probe, continuity of the cable, and that there are no continuity interruptions. | |
| E2 | Heating flow temperature probe defective | Check probe and connection cable. | |
| E9 | Water temperature limiter or flue gas temperature limiter has locked the boiler. | Check boiler water charge pressure, temperature limiter, that the pump is not blocked, electronic board fuses, ensure proper purging of the device, Check water side of the thermal block. In devices with expelling bodies in the thermal block, check if they are mounted. | |
| EA | No flame ignition in boiler. | Check gas, flow and pressure, electrical supply, ignition electrodes also their cables, boiler flue gas evacuation tube, check gas/air mix ratio, review gas regulators and pressure reducers if present in the installation. | |
| F0 | Internal defect. | Check electrical supply to boiler and electrical contacts, ignition cables. If necessary, change electronic board. Check gas/air mix ratio. | |
| F1 | Fault codes like this require the intervention of specialized personnel. | Consult intervention manual. | |
| F7 | Flame seen inside the device with the appliance turned off. | Check electrodes, ensure the electronic board is not wet, check the boiler’s gas outlet. | |
| FA | Flame detected inside the appliance after closing gas valves. | Check boiler gas valve, clean condensate siphon, check the state of gas evacuation. | |
| Fd | The reset button has been pressed by mistake. | Press reset again. | |
| b1 | Coded connector not detected | Check connection and connect correctly, replace if necessary. | |
| b2 | Internal data error | Consult the Official Technical Service. | |
| b3 | Internal data error | Consult the Official Technical Service. |
Our advice
While some issues can be resolved by following the instructions in the table, we always recommend contacting a specialized technician if you’re not confident in performing the repair yourself. Safety comes first, and a professional will be able to ensure that your boiler operates correctly and safely.
Error codes in Junkers boiler
Error b3 in Junkers boiler
Error b2 in Junkers boiler
