How to fix Worcester Bosch Boiler C6 Error Code?

At some stage, you may get an error code such as C6 showing in the display panel on your Worcester Bosch boiler? In this blog post, we'll look at the cause of the C6 Error Code and give some actionable advice on what you can do.

C6 Boiler Error Code = Faulty Fan?

The boiler display panel will flash up a digital indication when something is not working as it should. For example, a C6 fault code signals that something is wrong with the boiler fan. The fan is an important part of any boiler, as it removes any toxic fumes via the flue to the outside of the building. The function of the fan is recognised and monitored via an air pressure switch (a key component in the boiler).

Don’t underestimate the importance of the boiler fan- it's an essential safety feature! It can detect when the fan is running and, at the same time, toxic exhaust gases to the outside without any human contact.

Many other codes could pop up at any time; here are just a few to be aware of: Code of 215 or 216 will pinpoint precisely what the fault is — if it's,
215: Your boiler has detected an abnormally low speed!
216: Your boiler fan speed is excessive!


What if the boiler fan doesn’t work?
If your fan stops running and it doesn't come back on, you should expect to see either the C7 or 214 error (fault) message appear - this could indicate there may be an issue with the fan speed!

So let's take a closer look at what could be causing such a major inconvenience in your home – read on!

C6 Error Code: Causes and Fixes

Several causes are possible if the fan has been correctly adjusted, yet the issue persists even after a reset:

1. The fan is broken.
Fix:

• Isolate the appliance.
• Remove the electrical supply to the boiler.
• Disconnect the connecting wire.
• Remove the fan.
• Replace the fan.
• Reconnect the wiring.
• Reconnect the appliance to the power source.
• Turn the appliance on.

2. The fan's wiring is either faulty or loose.
Fix:

• Isolate the appliance.
• Disconnect the electrical supply to the boiler.
• To ensure continuity, measure the fan cable.
• Replace the fan cable if none of the cores is conductive.
• Reconnect the electricity to the appliance.
• Turn the appliance on.

3. There is an issue with the PCB.
Fix:

• Make a note of the service settings before proceeding.
• Turn the appliance OFF.
• Remove the electrical supply to the boiler.
• Replace the control board PCB.
• Reconnect the electricity to the appliance.
• Turn the appliance on.
• Restore previously recorded service settings.

Faulty PBC (Printed Circuit Board)
The PCB is the communication centre of a boiler; it sends and receives signals to any component/s electronically, including the fan, pump, burner, thermostat, diverter valve, and gas valve.

Most PCB errors stem from old age, water damage or a dry joint/connection. A cracked circuit board or burned-out connections are two issues that are difficult to repair. A replacement PCB may be the only option. The real fault can only be diagnosed accurately by a qualified gas-safe engineer. If the PCB has failed, it’s not good news as typically they can cost from £200 to £500 plus installation costs. Sometimes it’s not worth spending that kind of money on an old boiler, and it might be time to consider replacing it (if it’s beyond economical repair).

How does a boiler technician diagnose the fan fault?

Serviceteam are Worcester Bosch accredited installers, so rest assured your boiler repairs are in safe hands. A broken fan is uncommon in boilers under ten years old, but they do happen. During the diagnosis process, a thorough check of the electronics going to and from the fan will be conducted.

• A fan might have a variety of problems.
• A worn-out shaft or worn bearings could be present if the fan is aged. As a result, the fan would become rigid, unable to spin properly, and unable to increase speed to remove toxic gasses via the flue.
• Fan bearings are replaceable. However, it makes sense to replace the fan due to labour costs.

What causes WB boiler to lock out when the fan speed is too low?

The fan is the device that starts up first. A boiler will lock out if the fan is not working a sit, which can threaten safety.

In this instance, the C6 215 error is displayed as a warning that the fan is causing a problem. Although a low-speed fan provides a moderate draft to remove some flue gases, it won't remove them all. As a safety precaution, the boiler locks out to protect all inside a property.

Is there a DIY fix for a C6 fault?

No, there isn’t, and we would not recommend even the keenest DIY-er to take a chance. When dealing with gas appliances and toxic fumes. It is always best to call the professionals with a Worcester Bosch boiler C6 fault code – safety is always the first priority! Attempting a fix without gas safety qualifications can have serious consequences.

If you’re having problems with your boiler - contact serviceteam and book a visit from one of the gas engineers; remember, we are WB-approved installers, so we are familiar with all types of WB boilers - including yours! We endeavour to return your heating and hot water once we have accurately diagnosed the problem.

Contact serviceteam now and book your engineer today!