How To Fix Worcester Bosch C6 Fault Code and Causes
When your Worcester boiler shows a C6 fault code, your boiler often stops because the fan does not run correctly. The fan keeps combustion safe and moves flue gases outside. A faulty fan can affect performance and safety. This guide explains what worcester bosch C6 fault code means, how C6 215 and C6 216 differ, what usually triggers the code, and what a qualified engineer checks to fix it.
Table of contents
- Worcester Bosch C6 fault code overview
- What does the Worcester C6 fault code mean
- The role of the boiler fan
- C6 fault code variations
- Causes of the Worcester C6 error code
- Diagnosing and fixing the Worcester Bosch C6 error code
- Repair vs replacement
- Safety precautions and why you should call a professional
- How to reduce the risk of future C6 faults
- Conclusion
- Frequently Asked Questions
Worcester Bosch C6 fault code overview
C6 tells you your boiler fan has a problem. The boiler relies on the fan to pull air in for combustion and push flue gases out through the flue. When the fan runs too slow or too fast, the boiler can struggle to control combustion. The boiler may then stop to protect your home. Call a Gas Safe engineer because the fault involves a gas appliance.
What does the Worcester C6 fault code mean
C6 means your boiler detects a fan fault. The boiler control can also report sensor related issues when the fan fails to support stable combustion. A fan fault can increase strain on other components and reduce efficiency. You should not ignore C6 because the fan supports safe flue operation. A qualified engineer can confirm the cause and restore safe performance.
The role of the boiler fan
The boiler fan supports two key jobs. It drives airflow for combustion so the boiler burns gas correctly. It also helps move flue gases through the flue and out of your property. When the fan fails, the boiler cannot control combustion safely. The boiler may stop, show C6, and refuse to run until an engineer fixes the root cause.
C6 fault code variations
Worcester boilers often show extra numbers with C6. C6 215 means the boiler detects fan speed too high. C6 216 means the boiler detects fan speed too low. These variations help an engineer narrow down the issue faster. The engineer can then test the fan, wiring, and control signals to confirm what drives the speed error.
Causes of the Worcester C6 error code
Fan related issues
Fan faults often trigger C6. The fan motor can fail, the impeller can jam, or moisture can enter the unit. Blocked or frozen condensate pipework can also create conditions that lead to fan or flue related problems. Water near the flue area can also affect performance. An engineer checks airflow, movement, and signs of moisture or blockage.
Wiring and connection problems
Loose connectors, damaged cables, and poor contact can disrupt fan control. The boiler then reads the wrong speed or loses the fan signal. Engineers check the harness, plug connections, and the control box terminals. They also confirm correct voltage and continuity. This step often reveals a simple fix such as securing a loose connector or replacing a damaged cable.
PCB concerns
The PCB controls signals to the fan and reads fan feedback. If the PCB misreads fan speed or fails to drive the fan correctly, C6 can appear. A defective fan cable can also mislead the PCB. Engineers test outputs and inputs with the right tools. They then decide whether the job needs a fan repair, a cable replacement, or a PCB replacement.
Diagnosing and fixing the Worcester Bosch C6 error code
A qualified engineer follows a clear process. They inspect the fan harness and connectors. They check the control box connections. They test fan operation and confirm smooth impeller movement. They use a multimeter to confirm correct voltage at the fan motor terminals. They then check the PCB signals. After diagnosis, they repair the fault or replace the failed part.
Repair vs replacement
A minor issue like a loose connector or light debris can allow a repair and a quick return to service. A damaged motor, worn bearings, or severe corrosion often calls for a fan replacement. An engineer will weigh cost, reliability, and safety before they decide. They can also advise on boiler age and overall condition so you avoid repeat faults.
Safety precautions and why you should call a professional
Do not attempt a DIY fix for C6. The fault links to combustion, flue safety, and electrical control. DIY work can cause injury, gas risk, or deeper boiler damage. Call a Gas Safe engineer as soon as you see C6. A qualified engineer can diagnose safely, fix the real cause, and confirm safe operation after the repair.
How to reduce the risk of future C6 faults
Book annual boiler servicing and ask the engineer to check fan condition and flue performance. Keep the area around the boiler clear and dry. Ask the engineer to inspect condensate pipe routing before winter. Routine checks help you spot wear early and avoid breakdowns. Clean components and clear airflow support efficient running and reduce strain on the fan.
Conclusion
Worcester Bosch C6 fault code points to a boiler fan issue that can affect safe combustion and flue operation. C6 215 and C6 216 help narrow it down to fan speed too high or too low, but the cause often sits in the fan, wiring, moisture, condensate problems, or the PCB. Avoid DIY fixes and book a Gas Safe engineer to diagnose and repair it safely. Keep up with annual servicing to reduce repeat fan faults and keep your boiler running efficiently.
Frequently Asked Questions
The C6 code indicates your boiler’s fan isn’t spinning at the right speed – it’s either going too fast, too slow, or not at all. The fan is crucial for removing dangerous gases, so this fault needs prompt attention.
Generally, no. This requires inspecting wiring or replacing the fan, which must be done by a Gas Safe registered engineer.
The 2951 fault code suggests an issue with the boiler’s water pressure. Low pressure can lead to heating inefficiencies or system shutdowns. Checking for leaks, refilling the system, and adjusting the pressure settings can help resolve this fault.
