Worcester Bosch Boiler Fault Codes Explained with Resolutions

Understanding Worcester Bosch Boiler Fault Codes

Are you the proud owner of a Worcester Bosch boiler, but find yourself puzzled by the mysterious fault codes that occasionally appear on its display? Don't worry, you're not alone. Many homeowners experience frustration when faced with these seemingly cryptic error messages. That's why we've created this comprehensive guide to help you navigate through the maze of Worcester Bosch boiler fault codes.

In this blog, we'll break down over 30 common fault codes and explain them in simple terms, ensuring that even those with limited technical knowledge can understand what's going on. We'll unravel the secrets behind these codes, allowing you to make an informed decision on whether you can resolve the issue yourself or if it requires professional intervention.

Our aim is to empower you with the knowledge needed to troubleshoot and fix common boiler problems effectively. We'll provide step-by-step instructions for each fault code, highlighting potential causes and offering practical solutions.

Whether you're a homeowner or a heating engineer looking to expand your knowledge, this blog is designed to be your go-to resource for Worcester Bosch boiler fault codes. By understanding these codes and their underlying causes, you can potentially save time, money, and unnecessary hassle by resolving issues promptly.

Worcester Bosch Fault Code FD - Power Interrupted

What does Fault Code FD mean and how can I fix it?

Fault code FD means that there is an interruption in the power supply to the boiler. In simple terms, your boiler has lost power. Firstly, you should check if there is a power outage, and ensure that the power supply can be restored. If this becomes a consistent problem then you should contact a professional to inspect the electrical connections. 

Worcester Bosch Fault Code B1 - Code plug not detected

What does Fault Code B1 mean and how can I fix it?

Fault code B1 means that the code plug, which contains important configuration data, is not detected in your boiler. In simple terms this means that your boiler is unable to read the necessary settings it needs to. For this fault you will need to contact a qualified technician to examine the boiler's code plug and ensure it is properly connected or replaced if needed. 

Worcester Bosch Fault Code CC - Outdoor Sensor Defect 

What does Fault Code CC mean and how can I fix it?

As the name suggests, this boiler fault code means that there is a defect in the outdoor sensor. In simple terms this means that the sensor that measures the outdoor temperature is not functioning properly. There is no simple fix for this and it requires a qualified technician to attend and potentially replace the sensor itself. 

Worcester Bosch Fault Code A7 - Domestic Hot Water Sensor Defect

What Does Fault Code A7 mean and how can I fix it?

This fault code means that there is a defect in the sensor responsible for measuring domestic hot water temperature. In simple terms this means that the sensor that measures the temperature of hot water is not working or functioning correctly. Again this is an error that would require a professional engineer to check and potentially replace the sensor if it is broken. 

Worcester Bosch Fault Code B7 257 - Internal error

What does Fault Code B7 257 mean and how can I fix it?

This boiler fault code means that there is an internal error or potential problem with the control board. In simple terms this means that there is an issue with the internal electronics of the control board of the boiler. Much like the other faults above, it’s advised that you work with a qualified professional to remedy this issue. 

Worcester Bosch Fault Code C6 215 - Fan speed error

What does Fault Code C6 215 mean and how can I fix it?

This fault is specific to Worcester Greenstar boilers and means that the fan speed is too high. In simple terms, the speed of the fan is running much higher than normal. The fix for this would initially be to try restarting the boiler. If the fan speed does not return to normal, it may require an engineer to look at it. 

Worcester Bosch Fault Code 9A 362 - Heat Control Module (HCM)

What does Fault Code 9A 362 mean and how can I fix it?

This fault code means that the Heat Control Module (HCM) in your Worcester Bosch boiler is defective. In simple terms, there is a problem with the control component responsible for regulating heat in the boiler. To fix this issue, call a boiler engineer to inspect and potentially replace the faulty Heat Control Module (HCM) or control box.

Worcester Bosch Fault Code A1 281 - Blocked pump

What does Fault Code A1 281 mean and how can I fix it?

This fault code means that the pump in the boiler is blocked or running with air in the system. In simple terms the pump that circulates water through the boiler is not functioning properly. Try turning the boiler off and on again to reset the pump. If the issue persists, contact a boiler engineer to inspect and resolve the blockage or air in the system.

Worcester Bosch Fault Code EF 349 - Minimum burner load

What does Fault Code EF 349 mean and how can I fix it?

This fault code suggests that the primary flow of the boiler is operating at the minimum burner level. In simple terms, the flow of water through the boiler is too low to maintain proper burner operation. To fix this, check the safety temperature valve and ensure it is within the recommended range. Consider replacing the temperature sensor if needed.

Worcester Bosch Fault No Code 212 - Flow temperature high

What does Fault Code 212 mean and how can I fix it?

The fault codes means that the boiler temperature is too high. In simple terms, the water circulating through the boiler is hotter than it should be. Check if the safety temperature limiter has tripped and needs replacing. Restart the boiler to reset the high limit thermostat and prevent further overheating.

Worcester Bosch Fault Code EA 229 - Loss of ionisation detected

What does Fault Code EA 229 mean and how can I fix it?

This fault code means there is a loss of ionisation signal before burner start or during operation. In simple terms the boiler is having trouble detecting the presence of a flame. Check the temperature sensor installation and ensure the pressure is within the recommended range. Inspect connections and reset the boiler if necessary.

Worcester Bosch Fault Code E5 218 - Flow temperature sensor too high

What does Fault Code E5 218 mean and how can I fix it?

This fault means the flow temperature sensor or hot water temperature sensor in the burner control unit is detecting a high temperature. In simple terms the sensor responsible for measuring the water temperature is reporting higher than expected readings. If the temperature sensor is defective, it will need to be replaced by a qualified heating engineer.

Worcester Bosch Fault Code 2964 B - Sensor too high (heat exchanger temperature)

What does Fault Code 2964 B mean and how can I fix it?

This fault means the heat exchanger temperature sensor is detecting a value outside the expected range for the primary flow temperature. In simple terms the sensor responsible for measuring the heat exchanger temperature is providing abnormal readings. To resolve this, turn the modulating gas valve anticlockwise to trigger a reset position for the safety or flow temperature.

Worcester Bosch Fault Code 1017 W - Low water pressure

What does Fault Code 1017 W mean and how can I fix it?

The water pressure in the boiler is too low. If the issue is related to domestic hot water, the vent system or pressure sensor may need to be replaced. Consider topping up the water if necessary.

Worcester Bosch Fault Code 226 - Safety sensor code

What does Fault Code 226 mean and how can I fix it?

A safety sensor has triggered an error and is recorded in the history menu. In simple terms a safety component in the boiler has detected a fault. Try restarting the boiler to clear the error. If the code persists, it may indicate a more significant problem, and you should consider purchasing a new boiler.

Worcester Bosch Fault Code EA - No flame detected

What does Fault Code EA mean and how can I fix it?

The boiler has failed to ignite or maintain a flame. To fix, check if there is a gas supply, ensure the gas valve is open, and inspect the ignition leads for damage or blockage. If necessary, contact a qualified heating engineer for assistance.

Worcester Bosch Fault Code D1 - Low water pressure

What does Fault Code D1 mean and how can I fix it?

This fault means that your water pressure is too low. In simple terms, the water level is insufficient. To fix, check the pressure gauge on the boiler, and if it's below the recommended level (typically between 1 and 1.5 bar), repressurize the system following the manufacturer's instructions.

Worcester Bosch Fault Code D5 - Flue gas overheat

What does Fault Code D5 mean and how can I fix it?

The temperature of the flue gases is too high. In simpler terms, your boiler is overheating. To fix, ensure that the boiler's air intake and flue are not blocked. Check if the system water pressure is within the recommended range. If the problem persists, contact a qualified heating engineer for assistance.

Worcester Bosch Fault Code C6 - Fan fault

What does Fault Code C6 mean and how can I fix it?

The boiler's fan is not operating correctly. Check for any obstructions or damage to the fan. If there is no visible issue, contact a qualified heating engineer to inspect and potentially replace the fan.

Worcester Bosch Fault Code EA229 - Flame sensing fault

What does Fault Code EA229 mean and how can I fix it?

The boiler is unable to detect the flame. In simple terms, the boiler is having trouble sensing whether the flame is present. To fix, clean the flame sensing electrode with a soft cloth or brush. If the fault persists, contact a qualified heating engineer for further investigation.

Worcester Bosch Fault Code EA227 - Ignition fault

What does Fault Code EA227 mean and how can I fix it?

The boiler is unable to ignite. In simple terms, the boiler is having trouble starting up. To fix, check if the gas supply is available and the gas valve is open. Inspect the ignition leads for any damage or blockage. If necessary, contact a qualified heating engineer for assistance.

Worcester Bosch Fault Code EA222 - Control board communication fault

What does Fault Code EA222 mean and how can I fix it?

There is a communication problem between the control board and other components. In simple terms, the boiler's internal communication system is experiencing an issue. A possible solution to this is to power off the boiler for a few seconds and then turn it back on. If the fault persists, contact a qualified heating engineer for further diagnosis.

Worcester Bosch Fault Code C7 - Fan speed too low

What does Fault Code C7 mean and how can I fix it?

The speed of the boiler's fan is too low. In simple terms, the fan that provides air to the boiler is not running at the proper speed. To fix this, check for any obstructions or damage to the fan. If the fan speed control is adjustable, ensure it is set correctly. If needed, contact a qualified heating engineer to inspect and potentially replace the fan.

Worcester Bosch Fault Code D6 - Condensate pipe blocked

What does Fault Code D6 mean and how can I fix it?

The condensate pipe, which removes waste water from the boiler, is blocked. In simple terms, the pipe that carries water away from the boiler is obstructed. To fix, inspect the condensate pipe for any blockages or frozen sections. Thaw any frozen areas and clear any debris or obstructions. Consider insulating the pipe to prevent future freezing. If the problem persists, contact a qualified heating engineer for assistance.

Worcester Bosch Fault Code EA212 - Circulation fault

What does Fault Code EA212 mean and how can I fix it?

The boiler is not detecting proper water circulation. In simple terms the water is not circulating through the boiler correctly. To fix, check that the system's pump is functioning correctly. Ensure that the pump speed control is set appropriately. If necessary, contact a qualified heating engineer to inspect and potentially replace the pump.

Worcester Bosch Fault Code EA118 - Flame sensing electrode fault

What does Fault Code EA118 mean and how can I fix it?

The boiler's flame sensing electrode is faulty. In simple terms, the part that detects the flame in the boiler is not working properly. To fix this fault, clean the flame sensing electrode with a soft cloth or brush. If the fault persists, contact a qualified heating engineer to inspect and potentially replace the electrode.

Worcester Bosch Fault Code D7 - Primary flow fault

What does Fault Code D7 mean and how can I fix it?

There is a problem with the flow of water through the primary circuit. In simple terms, the water flow within the boiler's primary circuit is disrupted. To fix this, check for any obstructions or restrictions in the primary circuit. Ensure that all valves are fully open. If necessary, contact a qualified heating engineer for assistance.

Worcester Bosch Fault Code EA110 - Gas valve fault

What does Fault Code EA110 mean and how can I fix it?

The boiler's gas valve is not operating correctly. In simple terms there is an issue with the component that controls the flow of gas to the boiler. Check if the gas supply is available and the gas valve is open. Inspect the wiring and connections to the gas valve for any damage or loose connections. If needed, contact a qualified heating engineer for further diagnosis and potential replacement of the gas valve.

Worcester Bosch Fault Code EA227 - Gas valve control fault

What does Fault Code EA227 mean and how can I fix it?

There is an issue with the control of the gas valve. In simple terms, the boiler is having trouble controlling the flow of gas. To fix this, check the wiring and connections to the gas valve for any damage or loose connections. If necessary, contact a qualified heating engineer to inspect and potentially replace the gas valve control component.

Worcester Bosch Fault Code EA221 - Safety temperature limiter fault

What does Fault Code EA221 mean and how can I fix it?

The safety temperature limiter in the boiler has been triggered. In simple terms, the boiler has shut down to prevent overheating. To remedy this, Check for any blockages or restrictions in the system that may be causing overheating. Ensure proper water circulation and system pressure. If the fault persists, contact a qualified heating engineer to investigate and resolve the issue.

Worcester Bosch Fault Code EA279 - Boiler configuration fault

What does Fault Code EA279 mean and how can I fix it?

There is an error in the configuration of the boiler. In simple terms, the boiler's settings or programming are incorrect. To fix this, reset the boiler by powering it off for a few seconds and then turning it back on. If the fault persists, contact a qualified heating engineer to reconfigure the boiler settings.

Worcester Bosch Fault Code EA262 - Gas valve fault during operation

What does Fault Code EA262 mean and how can I fix it?

There is a fault with the gas valve during the boiler's operation. In simple terms, the gas valve is not functioning properly while the boiler is running. For this fault you should contact a qualified heating engineer to inspect and potentially replace the faulty gas valve.

Congratulations! You've successfully delved into the realm of Worcester Bosch boiler fault codes and emerged as a troubleshooting expert. We hope this comprehensive guide has demystified the complexities behind these error messages and provided you with the knowledge and confidence to tackle common boiler issues head-on.

Remember, understanding the fault codes is just the first step. By following the step-by-step instructions and implementing the suggested solutions, you can effectively resolve problems and keep your Worcester Bosch boiler running smoothly. However, it's essential to prioritize safety at all times. If you encounter a fault code that requires professional assistance or involves complex repairs, don't hesitate to reach out to qualified technicians for support.

We encourage you to bookmark this guide as a valuable resource for future reference. By regularly maintaining and troubleshooting your boiler, you can prolong its lifespan, optimize its performance, and ensure the comfort of your home.