Baxi E131 Fault Code – What It Means and How to Fix It
If your Baxi boiler is displaying the E131 fault code, it means the boiler has entered a flue overheat lockout. This often happens after a power cut or due to poor heat dissipation. While a simple reset might resolve the issue, further action may be required if the fault returns. Below, we explain what the E131 code means, outline the key causes, and provide step-by-step troubleshooting tips.
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What Is the Baxi E131 Error Code?
The E131 error code indicates that the flue temperature has exceeded safe limits. This causes the boiler to shut down to prevent damage. One common cause is a power cut, which can disturb the system’s sensors and cause it to enter lockout mode.
How to Troubleshoot and Fix the E131 Error Code
Time needed: 10 minutes
Follow the below steps to Fix the Baxi E131 Error Code
- Reset the Boiler
A boiler reset is often the quickest solution. Here’s how: Turn the temperature control knob fully anticlockwise. Hold it in that position until the lockout light turns off. Then turn the knob back to your desired temperature setting. If the boiler restarts and stays on, the issue may be resolved.
- Inspect the Flue and Flue NTC Sensor
Problems with the flue or its temperature sensor (NTC) can cause the boiler to overheat. Check for any loose or damaged flue connections. Ensure the NTC sensor is clean and properly fitted. Blocked or incorrectly installed flues may trap heat, triggering the E131 lockout.
- Bleed Your Radiators
Trapped air inside radiators can restrict water circulation, leading to overheating. Use a radiator key to release any trapped air. Have a cloth or container ready to catch water drips. After bleeding, check your boiler pressure and top it up if needed. This simple step can improve circulation and reduce the risk of faults.
- Check the Heating Pump
A faulty or stuck pump can prevent proper water flow, causing the system to overheat. Listen for any strange noises or vibrations from the pump. Ensure it’s running when the heating is on. If it’s not working, an engineer may need to repair or replace it.
- Verify the Thermostat Settings
Sometimes, the issue lies in the thermostat. Make sure it’s set to a realistic and comfortable temperature. If the thermostat is faulty or inaccurate, it can cause overheating and lockouts. A qualified engineer can check and recalibrate or replace it if necessary.
- Call a Qualified Engineer
If the E131 code appears frequently or doesn’t go away after trying the steps above, it’s time to call a Gas Safe registered engineer. Persistent issues may indicate flue installation problems, faulty sensors or wiring, or control board errors. A professional will be able to diagnose the root cause and carry out safe, effective repairs.
Final Thoughts
The Baxi E131 fault code is a protective mechanism that signals a flue temperature issue—often resolved with a simple reset. However, if problems persist, it’s important to check components like the flue, pump, and thermostat, and consult a qualified engineer when necessary. Regular boiler servicing and maintenance can help prevent such faults and keep your home warm and safe all year round.
Frequently Asked Questions
E110, E125, and E131 error codes signify potential overheating issues in boilers. To resolve this, immediately turn off the boiler and bleed radiators to release trapped air, optimizing water circulation. Check the pump for malfunctions, verify the thermostat’s accuracy, and reset the boiler.
The E135 fault code on a Baxi boiler indicates an internal gas supply interruption requiring professional diagnosis and repair. A simple reset can be attempted by setting the selector switch to ‘R’ for 5 seconds before calling an engineer.
If the E151 error appears, press the reset button. If that doesn’t clear the fault, switch off the boiler’s power supply for at least 10 seconds, then turn it back on. The error still shows, contact an authorized service center for help. Also, check the position of the ignition and flame sensing electrode, as incorrect positioning can trigger this fault.
