Worcester C6 Fault Code on Boiler Causes, Meaning & How to Fix

James Elston
Written by James Elston
Updated on 14th November 2023
Posted on 4th October 2023
Topic: Boiler Advice
Worcester C6 Fault Code Causes, Meaning & How to Fix

Worcester Bosch C6 Fault Code Meaning, Causes and How to Fix it

If you are unfortunate to be reading this then you will likely have encountered the Worcester C6 fault code on your boiler and wondered what it means and how you can resolve it.

In this fix all guide from our experts at Boiler Central, we will unravel the mystery behind the Worcester Bosch C6 fault code, discuss its variations, explain the common causes, and provide guidance on diagnosing and rectifying the issue with the help of a qualified boiler engineer.

Armed with this knowledge, you will not only be better prepared to tackle the C6 fault code (call a Gas Safe engineer) and appreciate the importance of regular boiler servicing and professional assistance in keeping your boiler running smoothly and efficiently

So, let’s dive into the world of Worcester boilers, boiler fans, and the notorious C6 fault code!

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Worcester Bosch C6 Fault Code Overview

Your boiler is probably the most important part of your home’s comfort, and therefore understanding the importance of diagnosing and fixing the Worcester Bosch C6 error fault code is essential for maintaining its efficiency and safety.

  • The Worcester C6 fault code indicates an issue with the boiler fan, which can lead to decreased performance and safety hazards.
  • Professional assistance from a certified engineer is essential for diagnosing and fixing the C6 fault code safely.
  • Preventative maintenance such as routine inspections, cleaning components, and verifying qualifications of engineers can help reduce the risk of encountering this error.

What Does the Worcester C6 Fault Code Mean?

The Worcester C6 fault code is a clear indication of an issue with your Worcester Bosch boiler fan. This code signals that the fan is experiencing difficulties, which may affect the heat exchanger temperature sensor, the flow temperature sensor, and the hot water temperature sensor.

A malfunctioning fan can lead to various problems in your boiler, such as poor heat distribution and increased strain on other components. Thus, comprehending the C6 fault code along with its variations holds significant value for your boiler’s efficiency and safety.

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The Role of the Boiler Fan

The boiler fan is a vital component in the proper functioning of your Worcester Bosch boiler. It serves to expel toxic flue gases from the flue to the exterior of the building, ensuring a safe environment inside your home. Additionally, the fan provides air for combustion in the boiler, facilitating the efficient operation of the combustion process.

The appearance of a C6 fault code signifies a fan malfunction, a condition that can negatively influence your boiler’s performance and safety.

C6 Fault Code Variations

The C6 error code is not a one-size-fits-all issue, as it comes in two variations: C6 215 (Fan speed error – fan running too fast) and C6 216 (Fan speed error – fan running too slow).

These supplemental codes aid in pinpointing the specific issues with the boiler fan, which could impact the safety temperature valve, heat control module, modulating gas valve, or even other components.

Read more about Worcester Bosch boiler error codes here

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Causes of the Worcester C6 Error Code

Having explained the meaning of the Worcester C6 fault code and its variations, we now need to delve into the common causes that lead to it. Potential causes may include fan problems, wiring issues, and PCB concerns, which can impact the primary flow temperature.

Recognising and rectifying these causes will help maintain the efficient and safe operation of your boiler, ensuring it operates within the minimum burner load requirements.

Fan-Related Issues

Fan-related issues are among the most common causes of the C6 fault code. Some possible causes of the C6 error code on your boiler include:

  • A broken fan
  • A fan speed that is either too high or too low
  • Moisture inside the unit
  • A blocked or frozen condensate pipe
  • Water down the outer part of the flu
  • Faulty wiring and connections
  • Loose wiring and connections

These issues can lead to decreased boiler performance, increased energy consumption, and even potential safety hazards if left unaddressed.

Wiring and Connection Problems

Wiring and connection problems are another common cause of the C6 fault code. Faulty wiring sections, loose connections, and miswired connections can all result in the C6 error appearing on your boiler.

Rectifying these issues, such as adjusting a modulating gas valve anticlockwise, can prevent additional damage to your boiler and facilitate its optimal performance.

PCB Concerns

PCB (Printed Circuit Board) concerns can also lead to the appearance of the C6 fault code. The PCB is the communication center of your boiler, responsible for sending and receiving signals to and from relevant components, such as:

  • the fan
  • the pump
  • the burner control unit
  • the thermostat
  • the diverter valve
  • the gas valve

Potential PCB concerns that may lead to the C6 fault code include a broken fan, a low fan speed detected by the PCB, and a defective fan cable.

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Diagnosing and Fixing the Worcester Bosch C6 Error Code

Upon identifying the cause behind the Worcester C6 fault code, it becomes imperative to rectify it swiftly and effectively.

A certified boiler engineer is your best ally in diagnosing and fixing the C6 fault code, as they possess the expertise and tools necessary to resolve the issue accurately and safely.

How Boiler Engineers Identify Fan Faults

Boiler engineers have a systematic approach to identifying fan faults and determining the cause of the C6 fault code. They begin by:

  1. Inspecting the fan harness and connector
  2. Verifying the control box connections
  3. Testing fan operation
  4. Checking for a faulty PCB

Engineers identify fan faults by:

  • Checking over all the connections and securing any loose ones as required, which could be a potential fan fault
  • Using their multimeter to confirm the correct voltage at the fan motor terminal leads
  • Inspecting the fan impeller for smooth and free operation to ensure optimal performance.

Repair vs. Replacement

When dealing with the C6 fault code, you may need to weigh the pros and cons of repairing vs. replacing components. Repairing the fan can be a cost-effective solution if the problem is minor and can be quickly remedied. Conversely, replacing the fan is essential when the fan is severely damaged or beyond repair.

A qualified boiler engineer can help you assess the situation and determine the most suitable course of action to ensure the continued efficiency and safety of your boiler.

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Safety Precautions and the Importance of Professional Help

Alongside understanding the Worcester C6 fault code and its root causes, one must also acknowledge the necessity for professional help and safety measures when confronting this issue. Boilers are complex systems, and attempting to diagnose and fix the C6 fault code without proper training and expertise can lead to further damage or even injury.

It is always best to contact a qualified professional to help with any boiler issues, as they

Dangers of DIY Fixes

DIY fixes for the C6 fault code can be tempting, especially when you’re eager to restore your boiler’s functionality quickly. However, attempting to diagnose the C6 fault code independently carries a serious risk and should not be attempted, as it involves working on a gas appliance.

Incorrect diagnosis and repairs may lead to further damage to the boiler, while addressing the underlying cause may not be possible with DIY repairs, leading to recurring issues. Furthermore, the lack of proper knowledge and expertise could lead to personal injury or property damage.

Prompt contact with a Gas Safe engineer is essential upon encountering the C6 fault code.

Finding a Qualified Boiler Engineer

Locating a qualified boiler engineer to address the C6 fault code is easier than you might think. You can start by searching for Worcester Bosch accredited installers, who have the necessary skills and experience to diagnose and fix the issue.

Online directories and rating pages such as Checkatrade, Rated People, and TrustMark can also help you find a reliable and qualified engineer in your area.

To verify the qualifications of a boiler engineer, simply consult the Gas Safe Register. Securing assistance from a qualified professional can guarantee the longevity, safety, and efficiency of your boiler.

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Reducing the Risk of Worcester C6 Fault Codes

The old adage “prevention is better than cure” certainly applies when it comes to avoiding the Worcester C6 fault code. By implementing preventative maintenance measures and regularly inspecting your boiler, you can catch potential issues early and reduce the risk of encountering the C6 fault code in the future.

Such actions not only help you evade expensive repairs but also maintain the safety and efficiency of your boiler.

Routine Boiler Inspections

Regular boiler inspections carried out by a certified engineer can effectively diminish the risk of the C6 fault code occurrence. During a boiler inspection, the engineer will:

  • Assess the boiler for signs of wear and tear
  • Inspect the safety devices
  • Test the boiler for any faults
  • Examine the flue and ventilation to ensure proper functioning

Regular inspections can help identify potential issues with the boiler before they become more severe and expensive to fix. Moreover, routine maintenance can prolong the life of your boiler and guarantee its safe and efficient operation.

Keeping Components Clean and Clear

Keeping boiler components clean and unobstructed plays a vital role in ensuring its efficient operation. Regular inspection and cleaning of the fan can help prevent the occurrence of the C6 fault code by ensuring its proper functioning and eliminating any potential obstructions.

Additionally, keeping components clean and clear improves system hygiene and contributes to the overall aesthetics of your boiler. Simple steps like these can go a long way in reducing the risk of encountering the pesky C6 fault code.

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The Worcester C6 fault code is a common issue that can affect the efficiency and safety of your boiler. By understanding the variations of the C6 fault code, common causes, and the importance of the boiler fan, you can better address and prevent this issue from occurring.

Remember that professional assistance and safety precautions are paramount when dealing with the C6 fault code, and attempting DIY repairs could lead to further damage or injury.

Regular boiler inspections, clean components, and the help of a qualified boiler engineer are essential for maintaining the performance of your boiler and avoiding the C6 fault code. By implementing these preventative measures, you can enjoy the comfort and peace of mind that comes with a safe and efficient boiler.

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Frequently Asked Questions

What does C6 mean on a Bosch boiler?

C6 is a fan speed error code on a Bosch boiler, meaning the fan speed is too low. To resolve this issue, an inspection and possible replacement of the fan lead and connector is necessary.

What is the fault code on the Worcester 42cdi C6?

The Worcester 42cdi C6 fault code signals that the boiler fan is running at a lower speed than normal, or has an airflow restriction. A Gas Safe registered engineer will need to investigate further and test the fan and flue flow of the boiler.

How do I reset the fault code on my Worcester boiler?

To reset the fault code on your Worcester boiler, turn the temperature dial all the way down until you see the reset light and hold it there for 3-5 seconds. Then return the dial to its normal position and check if everything is working.

Why is the fault light flashing on my Worcester boiler?

The flashing blue light on your Worcester boiler could indicate a low gas pressure issue, usually caused by an upgrade to the boiler or pipe system. It is important to check for these upgrades in order to resolve the issue.

How do boiler engineers diagnose and fix the C6 fault code?

Boiler engineers diagnose and fix the C6 fault code by inspecting the fan harness and connector, verifying control box connections, testing fan operation, and analysing the PCB.

Written by
James Elston
James Elston Director Of Boiler Central
Posted on: 4th October 2023
Topic: Boiler Advice

James Elston is our resident boiler replacement and heating expert here at Boiler Central. With over 20 years experience in the boiler installation industry, James ensures that he knows everything there is about our Gas Safe boiler installations, energy saving and home heating solutions. This can be from simply procuring the latest best combi boilers, to reviewing and ensuring that Boiler Central maintains the highest standards across our boiler installation company.

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