Baxi 105 Fault Code: What a Flashing 30-Degree Light Means & How to Fix It
If you own a Baxi 105 boiler and notice a flashing 30-degree light, it usually indicates a Baxi fault code signaling a flame failure or ignition fault. While it can be worrying, understanding the cause can help you decide whether it’s a simple fix or requires a professional.
In this guide, we’ll explain what the Baxi 105 fault code means, possible causes, and troubleshooting steps to get your heating and hot water running again.
Table of contents
What Does the Baxi 105 Fault Code Mean?
On a Baxi 105e or 105he, a flashing 30-degree light indicates that the boiler is unable to ignite or keep the flame burning. In some cases, a red light flashing below the 30 or 60 number could also point to ignition or pump failure.
Common Causes of the Baxi 105 Fault Code
Flame Failure / Ignition Fault
The most common reason for the flashing 30-degree light is that the boiler can’t light the burner or keep the flame going.
Gas Supply Issues
If the gas supply is turned off or disrupted, the boiler won’t be able to ignite. Check other gas appliances (like your hob) to see if they’re working.
Blocked Condensate Drain
A blockage in the condensate drain pipe can stop your boiler from firing up. This is particularly common in freezing weather.
Low System Pressure
If your boiler’s pressure gauge reads below 0.5 bar, it could trigger the fault.
Pump Failure or Air in the System
A flashing light below the 60-degree mark can mean the pump has stopped working or there’s trapped air in the system.
Fan or Flue Fault
If the fan isn’t running or the flue is blocked, the boiler may lock out for safety reasons.
Troubleshooting Steps for the Baxi 105 Fault Code
Time needed: 5 minutes
Before calling an engineer, try these checks:
- Check the Gas Supply
Make sure the gas supply is on. Test other gas appliances to confirm they work.
- Inspect the Condensate Drain
Look for blockages and clear them if safe to do so.
- Check System Pressure
If the pressure is low, follow your manual to safely repressurize the system.
- Listen for the Fan
When the boiler tries to start, you should hear the fan running. If it’s silent, there could be a fan or PCB fault.
- Refer to the Baxi 105 Manual
Your manual will list specific fault codes and reset instructions.
When to Call a Gas Safe Engineer
If you’ve gone through the basic checks and your Baxi 105 fault code still shows, it’s time to call a Gas Safe registered engineer. They can diagnose issues such as faulty PCB relays, pump problems, or deeper ignition faults that require professional repair.
Conclusion
Regular servicing can prevent many issues with your Baxi 105 boiler. Annual maintenance helps keep the system efficient and reduces the chances of unexpected breakdowns.
Frequently Asked Questions
A flashing 30-degree light on a Baxi 105 boiler usually indicates a fault within the system. In many cases, it relates to ignition problems, overheating, circulation issues, or low system pressure.
You can reset the boiler by pressing and holding the reset button for a few seconds. After resetting, wait for the boiler to restart and check if the fault clears.
Yes, low boiler pressure can trigger the flashing 30-degree fault light. Check the pressure gauge and top up the system if the pressure is below the recommended level.
If the fault keeps returning, there may be an issue with the pump, fan, ignition system, or another internal component. A Gas Safe registered engineer should inspect the boiler safely.
No, repeated resetting is not recommended if the fault keeps returning. Continuous lockouts usually indicate an underlying issue that needs proper diagnosis.
