Worcester Boiler Error Codes
Worcester Bosch boiler error codes and what they mean
If your Worcester Bosch boiler is displaying an error code, the code can help identify what has caused the boiler to stop working. Worcester Bosch Greenstar boilers use a combination of letters, numbers and symbols to indicate operating conditions, warnings and faults.
Some boiler issues can be resolved with a simple reset or by checking the boiler pressure. However, many Worcester Bosch fault codes indicate a problem that needs to be diagnosed and repaired by a qualified Gas Safe registered engineer.
At Aigburth Plumbing & Heating, we diagnose and repair Worcester Bosch boilers throughout Liverpool. If your Worcester boiler has developed a fault, we can investigate the problem and, where possible, offer a fixed-price repair.
Below you’ll find Worcester Bosch error codes and fault information covering a range of popular Greenstar boilers, including the Greenstar 8000, Greenstar 4000, CDi, Greenstar i, Greenstar Ri, Greenstar Heatslave and GB162.
If you know the error code displayed on your Worcester boiler, you can use the information below to find out what it means and whether you may need an engineer.
Worcester Bosch problems
There is a lot of issues that can happen with your Worcester
What are Worcester boiler error codes?
The Worcester Bosch error codes will tell you what is wrong with your boiler. Depending what the error code is you can fix it yourself or you will need to get a gas safe engineer to fix it for you.
Some of the errors you will be able to clear yourself but a lot of them you will need the help of our team to diagnose the issues and get them fixed
Common Worcester Bosch boiler problems
Worcester Bosch boilers are designed to display information when the boiler is operating, when it needs attention or when a fault has caused it to stop working.
A Worcester boiler problem doesn’t always mean that a major component has failed. Depending on the boiler model and the code being displayed, the problem could be something relatively simple, such as low system pressure, a problem with the condensate pipe or the boiler needing a reset. Other fault codes can indicate problems with components such as the fan, pump, sensors, ignition system or gas valve.
Some of the most common Worcester Bosch boiler problems we deal with include:
- Worcester boiler showing an EA fault
- Boiler repeatedly going into lockout
- Boiler needing to be reset regularly
- Boiler losing pressure
- Boiler not firing up
- No heating or hot water
- Boiler showing a flashing blue light
- Frozen or blocked condensate pipe
- Fan fault codes
- Overheating and temperature sensor faults
- Ignition and flame detection problems
- Boiler displaying an error code but not working
The exact meaning of a fault code depends on the Worcester Bosch model you have. This is important because the same or similar code can have different meanings on different Worcester boilers.
If your boiler is displaying a fault code, make a note of the complete code, including any numbers that appear alongside the letters. This can help a Gas Safe registered engineer identify where to start when diagnosing the problem.
What do Worcester boiler error codes mean?
Worcester Bosch boilers use letters, numbers and symbols to tell you what is happening with the appliance. The exact way the code is displayed depends on the Worcester boiler model.
Some codes are simply showing that the boiler is carrying out a particular operation, while others indicate that the boiler has detected a fault and has stopped operating.
For example, a Worcester boiler may display:
- EA – commonly associated with an ignition or flame detection problem.
- C6 – commonly associated with a problem with the boiler fan on some Greenstar models.
- E9 – can indicate that a safety temperature limiter has operated.
- F0 – can indicate an internal boiler fault.
- A1 – on some models, can indicate a problem with the pump or water circulation.
- FD – on some models, indicates that the reset button has been pressed.
The numbers displayed alongside the letters can provide additional information about the particular fault. For this reason, it is important to make a note of the complete error code, rather than just the first two letters.
Not every Worcester code means the boiler is broken
It is also important to understand that not every code displayed by a Worcester Bosch boiler means there is a serious fault.
Some Worcester boilers display codes while they are starting, heating water, waiting for a demand or carrying out other normal operations. Other conditions can temporarily stop the boiler from operating and clear automatically once the cause has been resolved.
Worcester Bosch manuals describe these as different types of operating, blocking and locking conditions, depending on the boiler model.
If the boiler has locked out and continues to display a fault after a reset, the underlying problem will need to be diagnosed rather than repeatedly resetting the appliance.
Why does my Worcester boiler keep showing the same fault?
If you are regularly having to reset your Worcester Bosch boiler, don’t simply continue resetting it every time it stops working.
A reset can clear some fault conditions, but it does not necessarily repair the underlying problem. If the same error code keeps returning, there is likely to be an issue that needs investigating.
The fault could involve a component such as a sensor, fan, pump or ignition system, or there may be a problem elsewhere in the heating system.
Make a note of the complete fault code before contacting an engineer. This can provide useful information when diagnosing the boiler.
If you are unsure what a code means, you can find your Worcester boiler model below and check the relevant fault-code table.
How to reset a Worcester Bosch boiler
If your Worcester Bosch boiler has stopped working and is displaying a fault code, you may be able to reset it using the reset control on the boiler.
The exact reset procedure depends on the Worcester Bosch model you have, so it is best to check the user manual for your particular boiler. Worcester Bosch provides user manuals for its different Greenstar models, including the Greenstar 4000, Greenstar 8000, Greenstar i, CDi and other boilers.
Before resetting your Worcester boiler
If your boiler has stopped working, make a note of the complete fault code displayed before resetting it. For example, some Worcester boilers display a code such as EA 227 rather than simply EA.
You should also check the boiler pressure if your model has a pressure gauge or pressure display. Low system pressure can prevent some boilers from operating correctly.
How do I reset my Worcester boiler?
On many Worcester Bosch boilers, the reset control can be used to clear a fault and restart the appliance. The procedure varies between models.
For example, Worcester’s instructions for some Greenstar models state that the reset control should be pressed to reset the appliance. If the reset is successful, the boiler should return to normal operation. If the same fault code appears again, the underlying problem has not been resolved.
Older Worcester Bosch models can have a different reset procedure, so don’t assume that every Worcester boiler resets in exactly the same way.
My Worcester boiler won’t reset
If the boiler will not reset, or the same error code keeps coming back after a reset, don’t continue repeatedly resetting it.
Some Worcester Bosch fault codes cannot be cleared by a simple reset and require the underlying fault to be diagnosed. Worcester’s own manuals advise contacting a suitably qualified engineer where a fault cannot be cleared by the user.
Repeatedly resetting a boiler can also hide the fact that there is an underlying problem. If your Worcester boiler keeps going into fault or lockout, it is better to have the cause investigated.
If you need a Worcester Bosch emergency boiler repair in Liverpool, Aigburth Plumbing & Heating can diagnose the fault and advise you on the best repair.
Worcester Bosch EA error code
The EA error code is one of the more common fault codes displayed by Worcester Bosch boilers. It generally relates to the boiler not detecting a flame or losing the flame during operation, but the exact meaning can depend on the Worcester boiler model and the number displayed alongside the EA code.
For example, EA 227 is found on a number of Worcester Bosch models and indicates that the boiler has failed to detect a flame after ignition. A blocked or frozen condensate pipe can be one possible cause. Worcester Bosch specifically identifies repeated lockouts, an EA code and a gurgling noise when the boiler attempts to start as possible signs of a blocked condensate pipe.
EA 227 – Worcester boiler
If your Worcester boiler is displaying EA 227, there are several possible causes. These can include:
- A frozen or blocked condensate pipe
- A problem with the gas supply
- An ignition problem
- A flame detection or ionisation problem
- A problem with another component involved in safely starting the boiler
This means that an EA 227 code does not automatically mean that one particular component needs replacing. The boiler needs to be diagnosed to establish why it has failed to establish or maintain a flame.
Worcester EA fault in cold weather
If your boiler develops an EA fault during freezing weather, check whether the condensate pipe runs outside the property.
A frozen condensate pipe can prevent the boiler from operating and may cause an EA code. Worcester Bosch recommends checking for a frozen condensate pipe and, where it is safe to do so, thawing it with warm water rather than boiling water. The boiler can then be reset.
Only attempt this if the condensate pipe is at ground level and easily accessible. Do not attempt to thaw pipework that is at height. Worcester Bosch also specifically warns against using boiling water because this can damage the pipe.
What if the EA fault keeps coming back?
If you have reset your Worcester boiler and the EA fault returns, there is likely to be an underlying problem that needs investigating.
Don’t keep repeatedly resetting the boiler. A Gas Safe registered engineer can diagnose the cause of the fault and determine whether the problem is related to the condensate system, ignition, flame detection, gas supply or another boiler component.
When contacting an engineer, tell them the complete fault code, such as EA 227, along with the Worcester boiler model if you know it. This can help with the initial diagnosis.
If your Worcester Bosch boiler is displaying an EA fault and you need a boiler repair in Liverpool, Aigburth Plumbing & Heating can diagnose the problem and carry out the necessary repair.
Common Worcester Bosch fault codes
Below are some of the Worcester Bosch fault codes that homeowners commonly come across. The exact meaning of a code can vary depending on the boiler model and the numbers displayed alongside it, so always check the fault against the correct model of boiler.
C6 – Fan fault
A C6 fault is commonly associated with the boiler fan. On some Worcester Bosch models, C6 indicates that the fan speed is too low or that the boiler has detected a problem with the fan.
The fan is an important part of the boiler’s operation because it helps move combustion gases through the flue. A C6 fault may therefore require the fan, wiring or associated components to be checked by a qualified engineer.
E9 – Safety temperature limiter
An E9 fault can indicate that a safety temperature limiter has operated because the boiler has detected an excessive temperature or another condition requiring the boiler to shut down.
Depending on the Worcester model, possible causes can include problems with water circulation, system pressure, the pump, temperature sensors or an overheating condition.
If the E9 fault keeps returning after a reset, the cause needs to be investigated rather than repeatedly resetting the boiler. Worcester Bosch documentation advises that these faults should be dealt with by a competent qualified engineer.
F0 – Internal fault
An F0 fault generally indicates an internal boiler fault. The exact cause depends on the Worcester Bosch model.
Because an F0 fault can involve the boiler’s electronic controls or other internal components, it isn’t normally something that can be diagnosed or repaired by simply resetting the boiler.
F7 – Flame detected when the boiler should be off
An F7 fault can indicate that the boiler has detected a flame signal when the appliance should have stopped firing.
This is a fault that requires investigation rather than repeated resetting. Worcester Bosch lists F7 as a fault condition on several Greenstar models.
FA – Flame detected after the gas has been shut off
An FA fault can indicate that the boiler is detecting a flame signal after the gas supply to the burner has been shut off.
The cause needs to be diagnosed by a qualified engineer. Depending on the model, checks can include the flame detection system, wiring, control components and gas valve.
FD – Reset button pressed
An FD or Fd code can indicate that the reset button has been pressed incorrectly or that the boiler has detected a reset-button condition.
The exact display and meaning depends on the Worcester Bosch model. On some models, pressing the reset control again can clear the condition.
A1 – Pump or circulation problem
An A1 code is used on some Worcester Bosch models to indicate a problem involving the pump or water circulation.
The precise meaning depends on the boiler model, so check the relevant table below rather than assuming that every A1 code has the same cause.
E2 – Temperature sensor fault
An E2 code can indicate a problem with a temperature sensor, such as the central-heating flow temperature sensor.
Depending on the model, this can involve a sensor fault, wiring or an electrical connection. Diagnosis normally requires an engineer.
EA – Flame not detected
The EA fault is one of the most commonly searched-for Worcester Bosch codes. It generally indicates that the boiler has failed to detect a flame or has lost the flame during operation.
There are several possible causes, including ignition problems, gas supply problems, flame detection issues and, on some models, a frozen or blocked condensate pipe.
For more information, see our section above on the Worcester EA error code.
Worcester Greenstar 8000 error codes
The Worcester Bosch Greenstar 8000 range includes several different boiler versions, including the Greenstar 8000 Life and Style models and newer Greenstar 8000+ boilers.
The fault codes displayed can vary depending on the exact boiler and its control system. Worcester Bosch provides separate manuals for the different 8000 models, so if you are unsure which boiler you have, check the model name on the front of the appliance or refer to the user manual.
Below are some of the more useful Greenstar 8000 codes to know.
Greenstar 8000 common codes
| Fault code | What it means |
|---|---|
| 1017 | System water pressure is too low. The heating system may need topping up and the cause of the pressure loss should be investigated if it keeps happening. |
| 1021 | Hot water temperature sensor fault. |
| 1065 | Pressure sensor fault or the pressure sensor is not connected correctly. |
| 1073 | Flow temperature sensor short circuit. |
| 1074 | No signal from the flow temperature sensor. |
| 1075 | Temperature sensor at the heating block has a short circuit. |
| 1076 | No signal from the heating block temperature sensor. |
| 227 | No flame signal detected after ignition. |
| 228 | A flame signal has been detected when no flame should be present. |
| 229 | Flame has failed during burner operation. |
| 2920 | Fault with flame monitoring. |
| 2924–2927 | Fault associated with the boiler’s gas valve/electronic control system. |
| 2946 | Incorrect code plug detected. |
| 2948 | No flame signal at low burner output. |
| 2950 | No flame signal during the burner starting sequence. |
| 2963–2967 | Problems involving flow temperature, heat exchanger temperature or water circulation. |
| 2970 | Heating-system pressure has dropped too quickly. |
| 2971 | System pressure is too low. |
The exact fault description and recommended remedy can differ between versions of the Greenstar 8000. For example, Worcester’s documentation for the 8000 range identifies 1017 as low system pressure and 1021 as a hot-water temperature sensor fault.
Worcester Greenstar 8000 – 227 fault
A 227 fault indicates that the boiler has not detected a flame after attempting ignition.
There can be several possible causes, including problems with the gas supply, ignition system, flame detection system, condensate system, flue or other boiler components. Worcester’s technical documentation lists several possible causes, so the fault should not automatically be attributed to one particular component.
If the boiler continues to display the fault after a reset, it will need to be properly diagnosed by a qualified engineer.
Worcester Greenstar 8000 – 1017 fault
If your Greenstar 8000 displays 1017, the boiler has detected that the heating-system water pressure is too low.
You may be able to see the pressure on the boiler display. If the pressure is low, the system may need topping up according to the instructions for your particular installation.
If the pressure repeatedly drops after being topped up, don’t simply keep adding water. There may be an underlying problem such as a leak, expansion vessel issue or another fault within the heating system.
Worcester Greenstar 8000 – 2927 fault
The 2927 code is associated with the flame failing during burner operation on Greenstar 8000 models.
There are several possible causes, including problems with the gas supply, gas/air ratio, ignition or flame detection system, condensate system, flue or burner.
This is not a fault that should be diagnosed by dismantling the boiler yourself. A Gas Safe registered engineer will need to investigate the cause.
Worcester Greenstar 8000 – other fault codes
The Greenstar 8000 can display many additional codes, including codes relating to sensors, pressure, temperature, communication, the fan, gas valve and electronic controls.
If your particular code isn’t listed above, make a note of the complete code, including all numbers, and check the correct Worcester Bosch manual for your model. Worcester provides current manuals for Greenstar 8000 boilers through its website.
If your Worcester Greenstar 8000 has developed a fault and won’t restart, Aigburth Plumbing & Heating can diagnose Worcester Bosch boiler faults and carry out repairs in Liverpool.
Worcester Greenstar 4000 error codes
The Worcester Bosch Greenstar 4000 is a popular modern boiler with a digital display that can show operating information and fault codes.
The exact code displayed depends on the fault detected by the boiler. Worcester Bosch categorises its codes into different types, including normal operating codes, blocking faults and locking faults. A blocking fault can clear when the underlying condition is removed, while a locking fault normally requires the boiler to be reset.
If your Greenstar 4000 is displaying a fault, make a note of the complete code before resetting the boiler. This can help an engineer identify the problem.
Common Worcester Greenstar 4000 fault codes
| Fault code | What it means |
|---|---|
| 1021 | Fault with the hot water or cylinder temperature sensor, depending on the boiler configuration. |
| 224 | A safety-related fault has been detected and the boiler may need to be checked and reset by a qualified engineer. |
| 227 | The boiler has failed to detect a flame after ignition. |
| 228 | The boiler has detected a flame signal when a flame should not be present. |
| 1017 | Heating-system water pressure is too low. |
| E9 | A safety temperature or overheating condition has been detected, depending on the particular version of the boiler. |
| EA | The boiler has failed to establish or maintain a flame. |
| C6 | A fault associated with the boiler fan. |
The exact description can depend on the Greenstar 4000 version and the complete code displayed. Worcester Bosch provides separate operating manuals for the Greenstar 4000 Combi and System boilers.
Worcester Greenstar 4000 losing pressure
If your Greenstar 4000 is showing a low-pressure warning, check the pressure displayed on the boiler.
A small drop in pressure can sometimes be dealt with by topping up the heating system in accordance with the manufacturer’s instructions. However, if the pressure keeps dropping, there is likely to be an underlying reason that needs investigating.
Possible causes can include a leak somewhere on the heating system, a problem with the expansion vessel or another fault within the system.
The Greenstar 4000 also has a digital pressure gauge, allowing the system pressure to be monitored from the boiler display.
Worcester Greenstar 4000 won’t reset
If your Greenstar 4000 continues to display the same fault after a reset, don’t keep repeatedly resetting the boiler.
A reset can clear a locking fault, but it does not necessarily fix the reason the fault occurred. If the fault returns, the boiler needs to be diagnosed so that the underlying problem can be identified.
If your Worcester Greenstar 4000 has stopped working and you need a boiler repair in Liverpool, Aigburth Plumbing & Heating can diagnose the fault and advise you on the appropriate repair.
Worcester Greenstar CDi Highflow error codes
The Worcester Bosch Greenstar CDi Highflow is a floor-standing combination boiler designed to provide heating and high volumes of domestic hot water.
There are several versions of the Highflow CDi, including older 440 and 550 models, so the exact fault codes and descriptions can vary depending on the boiler’s age and version. Worcester Bosch provides separate manuals for the different generations of the appliance.
If your Greenstar CDi Highflow is displaying an error code, make a note of the complete code before attempting to reset the boiler. Worcester Bosch advises that faults shown in the error-code table should not be rectified by the homeowner and should be dealt with by a competent, qualified engineer.
Common Greenstar CDi Highflow fault codes
| Fault code | What it means |
|---|---|
| A1 | A problem involving the boiler pump or water circulation. |
| A7 | Domestic hot water temperature sensor fault. |
| A8 | Communication problem between the boiler’s electronic components. |
| B1 | Code plug not detected. |
| C6 | Fan speed is too low or a problem with the boiler fan has been detected. |
| E9 | The central-heating safety temperature limiter has operated. |
| EA | Flame has not been detected. |
| F0 | Internal boiler fault. |
| F7 | Flame has been detected when the boiler should be switched off. |
| FA | Flame has been detected after the gas supply to the burner has been shut off. |
| Fd | The reset button has been pressed incorrectly. |
These are among the fault codes documented by Worcester Bosch for its Greenstar boilers. The exact description can vary between Highflow versions, so the correct manual should always be checked against the boiler’s model and date of manufacture.
Greenstar CDi Highflow EA fault
The EA fault means that the boiler has failed to detect a flame. Worcester Bosch’s Highflow documentation lists possible causes including a problem with the gas supply, a frozen condensate pipe or a blocked flue outlet.
If your Highflow boiler is showing an EA fault, check the obvious external causes only if it is safe to do so. If the fault remains or keeps returning after a reset, the boiler should be diagnosed by a qualified Gas Safe registered engineer.
Greenstar CDi Highflow C6 fault
A C6 fault is associated with the boiler’s fan. Worcester Bosch describes C6 as the fan speed being too low on its Highflow documentation.
Because the fan is part of the boiler’s combustion and flue system, a C6 fault should not be investigated by removing boiler components yourself. A qualified engineer will need to establish the cause of the fault.
Greenstar CDi Highflow E9 fault
An E9 fault indicates that the safety temperature limiter in the central-heating flow has operated. This can be associated with an overheating or water-circulation problem.
If an E9 fault keeps returning after the boiler has been reset, the underlying cause needs to be investigated rather than repeatedly resetting the appliance.
Greenstar CDi Highflow fault keeps coming back
If your Worcester Greenstar CDi Highflow repeatedly goes into fault or lockout, don’t simply continue resetting it.
Make a note of the complete fault code and the boiler model, such as a Greenstar CDi Highflow 440 or 550. This information can help an engineer identify the correct fault information for your particular boiler.
If your Worcester Greenstar CDi Highflow has stopped working and you need a boiler repair in Liverpool, Aigburth Plumbing & Heating can diagnose the fault and advise you on the appropriate repair.
Worcester Greenstar CDi Compact error codes
The Worcester Bosch Greenstar CDi Compact is a wall-mounted combination boiler that was produced in several versions over the years. Worcester Bosch provides separate manuals for different production periods, so the exact meaning of an error code can depend on the particular CDi Compact model you have.
If your Greenstar CDi Compact is displaying a fault, make a note of the complete code, including any numbers displayed underneath it. For example, Worcester’s user instructions show an EA 227 fault being displayed on the boiler.
Common Greenstar CDi Compact fault codes
| Fault code | What it means |
|---|---|
| A1 | Problem involving the boiler pump or water circulation. |
| A7 | Domestic hot water temperature sensor fault. |
| A8 | Communication problem between boiler components. |
| B1 | Code plug not detected. |
| C6 | Fan speed too low or a problem with the boiler fan. |
| E2 | Central-heating flow temperature sensor fault. |
| E9 | Safety temperature limiter has operated. |
| EA | Flame has not been detected. |
| F0 | Internal boiler fault. |
| F7 | Flame detected when the boiler should be switched off. |
| FA | Flame detected after the gas supply has been shut off. |
| Fd | Reset button pressed incorrectly. |
The exact fault description can vary between different versions of the Greenstar CDi Compact, so the correct Worcester Bosch manual should be checked against the boiler model. Worcester’s own documentation also states that some faults cannot be cleared with a simple reset and require an engineer.
Greenstar CDi Compact EA fault
An EA fault means that the boiler has failed to detect a flame. Worcester Bosch’s instructions show that the fault can be accompanied by a three-digit number, such as EA 227.
If the fault occurs, you can follow the manufacturer’s reset instructions for your particular boiler. If the fault does not clear, or returns after the boiler has been reset, the underlying cause needs to be investigated.
Worcester Bosch advises homeowners not to attempt to rectify faults that require internal boiler work. A qualified Gas Safe registered engineer should diagnose the problem.
Greenstar CDi Compact C6 fault
A C6 fault is associated with the boiler fan. If the boiler displays C6, there may be a problem with the fan or its operation.
Because the fan is part of the boiler’s combustion and flue system, this is not something you should attempt to repair yourself. The boiler should be checked by a qualified engineer.
Greenstar CDi Compact E9 fault
An E9 fault indicates that the boiler’s safety temperature limiter has operated.
This can occur when the boiler detects an overheating or circulation-related condition. If the fault keeps returning after a reset, the cause needs to be diagnosed rather than repeatedly resetting the boiler.
Greenstar CDi Compact won’t reset
If your Greenstar CDi Compact displays the same fault after being reset, don’t continue repeatedly resetting it.
Worcester Bosch specifically explains that some fault codes cannot be cleared by a simple reset. If a fault cannot be reset by the user, a service engineer will be required.
If your Worcester Greenstar CDi Compact has stopped working and you need a boiler repair in Liverpool, Aigburth Plumbing & Heating can diagnose the fault and advise you on the appropriate repair.
Worcester Greenstar CDi Classic Regular error codes
The Worcester Bosch Greenstar CDi Classic Regular is a regular boiler that was available in different versions over several years. Worcester Bosch provides separate operating instructions for different production periods, so the exact fault-code information can vary slightly between models.
If your Greenstar CDi Classic Regular displays an error code, make a note of the complete code before resetting the boiler. This can help an engineer identify the problem and find the correct information for your particular boiler.
Common Greenstar CDi Classic Regular fault codes
| Fault code | What it means |
|---|---|
| C6 | Fan speed is too low or a problem with the boiler fan has been detected. |
| E9 | The central-heating safety temperature limiter has operated. |
| EA | The boiler has failed to detect a flame. |
| F0 | An internal boiler fault has been detected. |
| F7 | A flame has been detected when the boiler should be switched off. |
| FA | A flame has been detected after the gas supply to the burner has been shut off. |
| Fd | The reset button has been pressed incorrectly. |
These codes are documented in Worcester Bosch’s fault-code information for the CDi Classic range. Worcester specifically advises that the faults listed should not be rectified by the homeowner and should be dealt with by a competent, qualified engineer.
Greenstar CDi Classic Regular EA fault
An EA fault means that the boiler has failed to detect a flame.
There are several possible causes. Worcester Bosch’s fault-finding information includes a lack of gas supply, a blocked condensate outlet or a blocked flue outlet as possible causes of an EA fault.
If your boiler develops an EA fault, check the complete code displayed and follow the manufacturer’s instructions for your particular model. If the fault cannot be cleared or keeps returning, the underlying problem needs to be diagnosed by a qualified engineer.
Greenstar CDi Classic Regular C6 fault
A C6 fault indicates that the boiler has detected a problem with the fan, with Worcester Bosch describing this as the fan speed being too low.
The fan is an important part of the boiler’s combustion and flue system, so a C6 fault should be investigated by a qualified engineer rather than attempting to repair the boiler yourself.
Greenstar CDi Classic Regular E9 fault
An E9 fault indicates that the central-heating safety temperature limiter has operated.
This can be associated with an overheating or circulation problem. If the fault continues to return after the boiler has been reset, the cause needs to be investigated rather than repeatedly resetting the appliance.
Greenstar CDi Classic Regular won’t reset
If your Greenstar CDi Classic Regular has developed a fault and the reset does not clear it, don’t continue repeatedly resetting the boiler.
Worcester Bosch’s operating instructions state that if a fault cannot be cleared using the reset button, the fault-finding information should be consulted and a Gas Safe registered engineer contacted if necessary.
If your Worcester Greenstar CDi Classic Regular has stopped working and you need a boiler repair in Liverpool, Aigburth Plumbing & Heating can diagnose the fault and advise you on the appropriate repair.
Worcester Greenstar CDi Fi Regular error codes
The Worcester Bosch Greenstar CDi Fi Regular is a regular boiler from the older Greenstar range. As these boilers were produced in different versions, the exact fault-code display and descriptions can vary depending on the model and year.
If your Greenstar CDi Fi Regular displays a fault, make a note of the complete code before resetting the boiler. This can help identify the problem and ensures the correct information is used for your particular boiler.
Common Greenstar CDi Fi Regular fault codes
| Fault code | What it means |
|---|---|
| C6 | A problem with the boiler fan, such as the fan speed being too low. |
| E9 | The safety temperature limiter has operated. |
| EA | The boiler has failed to detect a flame. |
| F0 | An internal boiler fault has been detected. |
| F7 | A flame has been detected when the boiler should be switched off. |
| FA | A flame has been detected after the gas supply has been shut off. |
| Fd | The reset button has been pressed incorrectly. |
The exact meaning of a fault should always be checked against the correct manual for your Greenstar CDi Fi boiler.
Greenstar CDi Fi Regular EA fault
An EA fault means that the boiler has failed to detect a flame.
There can be several possible causes, including a problem with the gas supply, ignition system, flame detection system, condensate system or flue.
If your boiler develops an EA fault, make a note of the complete code and follow the manufacturer’s instructions for your particular model. If the fault remains after a reset or keeps returning, the underlying cause will need to be diagnosed by a qualified engineer.
Greenstar CDi Fi Regular C6 fault
A C6 fault is associated with the boiler fan.
The fan is an important part of the boiler’s combustion and flue system, so a C6 fault should be investigated by a qualified Gas Safe registered engineer rather than attempting to remove or repair boiler components yourself.
Greenstar CDi Fi Regular E9 fault
An E9 fault indicates that the boiler’s safety temperature limiter has operated.
This can be associated with an overheating or circulation problem. If the fault continues to return after resetting the boiler, the underlying cause needs to be investigated.
Greenstar CDi Fi Regular won’t reset
If your Greenstar CDi Fi Regular won’t reset, or the same fault code keeps appearing, don’t repeatedly reset the boiler.
A reset may clear the immediate lockout condition, but it does not necessarily fix the reason the fault occurred. A qualified engineer can diagnose the boiler
Worcester Greenstar i System 27 and 30 error codes
The Worcester Bosch Greenstar i System 27 and 30 are system boilers that were produced in several versions over the years. Worcester Bosch provides separate manuals for different production periods, so the exact fault-code information can vary depending on the boiler version.
If your Greenstar i System boiler displays a fault, make a note of the complete code before resetting it. This can help identify the problem and ensures that the correct information is used for your particular boiler.
Common Greenstar i System 27 and 30 fault codes
| Fault code | What it means |
|---|---|
| A1 | A problem involving the boiler pump or water circulation. |
| A8 | Communication problem between the boiler’s electronic components. |
| C6 | A problem with the boiler fan or fan speed. |
| E2 | Central-heating flow temperature sensor fault. |
| E9 | The safety temperature limiter has operated. |
| EA | The boiler has failed to detect a flame. |
| F0 | An internal boiler fault has been detected. |
| F7 | A flame has been detected when the boiler should be switched off. |
| FA | A flame has been detected after the gas supply has been shut off. |
| Fd | The reset button has been pressed incorrectly. |
The exact meaning of a code can depend on the particular generation of Greenstar i System boiler, so the correct Worcester Bosch manual should be checked against the model and date of manufacture. Worcester currently lists several versions of the Greenstar i System manuals.
Greenstar i System EA fault
An EA fault indicates that the boiler has failed to detect a flame.
There can be several possible causes, including a problem with the gas supply, ignition system, flame detection system, condensate system or flue.
If the EA fault remains after following the manufacturer’s reset procedure, or keeps returning, the underlying cause needs to be diagnosed by a qualified Gas Safe registered engineer.
Greenstar i System C6 fault
A C6 fault is associated with the boiler fan.
The fan is an important part of the boiler’s combustion and flue system. If a C6 fault keeps appearing, the boiler should be checked by a qualified engineer rather than attempting to remove or repair internal components yourself.
Greenstar i System E9 fault
An E9 fault indicates that the boiler’s safety temperature limiter has operated.
This can be associated with an overheating or circulation problem. If the fault continues to return after resetting the boiler, the underlying cause needs to be investigated.
Greenstar i System losing pressure
The Greenstar i System is a sealed heating system, so the boiler has a pressure gauge. Worcester Bosch states that the pressure should generally be around 1 bar when the heating is off, although the correct pressure can depend on the individual installation.
If the pressure repeatedly drops, don’t simply keep topping the system up. Repeated pressure loss can indicate a leak or another problem with the heating system that needs investigating.
Greenstar i System won’t reset
If your Greenstar i System boiler won’t reset, or the same fault keeps returning, don’t repeatedly reset it.
A reset can clear the immediate fault condition but does not necessarily repair the underlying problem. A qualified engineer can diagnose the boiler and determine what is causing the fault.
If your Worcester Greenstar i System 27 or 30 has stopped working and you need a boiler repair in Liverpool, Aigburth Plumbing & Heating can diagnose the fault and advise you on the appropriate repair.
Worcester Greenstar i Combi and System 9/24 error codes
The Worcester Bosch Greenstar i Combi and System 9/24 boilers are older Greenstar models that can display a combination of fault codes and numbers when a problem occurs.
Worcester Bosch produced several versions of the Greenstar i range over the years, so the exact meaning of a code can depend on the particular boiler and its production date. Worcester provides separate manuals for different versions of these boilers.
If your boiler displays a fault, make a note of the complete code, including the three-digit number that may appear alongside the letters. This is particularly important with faults such as EA 227, C6 215 or E2 222.
Common Greenstar i Combi and System 9/24 fault codes
| Fault code | What it means |
|---|---|
| EA 227 | The boiler has failed to detect a flame after ignition. |
| FA 306 | The boiler has detected a flame signal after the gas valve has closed. |
| C6 215 | Fan speed is too high. |
| C7 216 | Fan speed is too low. |
| C7 217 | The fan has stopped while the boiler is operating. |
| E2 222 | Central-heating flow temperature sensor fault. |
| E2 233 | Central-heating flow temperature sensor is disconnected. |
| E9 276 | The primary flow temperature has become too high. |
| C1 264 | The fan has stopped during boiler operation. |
| C4 273 | The boiler has been operating with the fan continuously for an extended period and has temporarily blocked. |
The exact code and description should always be checked against the correct manual for your particular Greenstar i boiler. Some of these codes relate to internal boiler components and require diagnosis by a qualified engineer.
Greenstar i EA 227 fault
The EA 227 fault indicates that the boiler has failed to detect a flame after attempting ignition.
There can be several possible causes, including a problem with the gas supply, ignition system, flame detection system, condensate system or flue.
A frozen condensate pipe can also cause an EA fault during cold weather. If the fault keeps returning after the manufacturer’s reset procedure, the underlying cause needs to be investigated rather than repeatedly resetting the boiler.
Greenstar i C6 or C7 fan fault
The C6 and C7 codes can relate to the boiler fan and its operation.
The fan is an important part of the boiler’s combustion and flue system. If one of these faults keeps appearing, the boiler should be checked by a qualified Gas Safe registered engineer rather than attempting to remove or repair internal components yourself.
Greenstar i E2 fault
An E2 fault relates to the central-heating flow temperature sensor.
The complete number is important because different E2 codes can provide additional information about the problem. For example, E2 222 and E2 233 relate to different sensor conditions.
If the fault remains after resetting the boiler, it will need to be diagnosed by an engineer.
Greenstar i E9 fault
An E9 276 fault indicates that the primary flow temperature has exceeded the permitted temperature.
This can be associated with an overheating or water-circulation problem. If the fault continues to return after resetting the boiler, the cause needs to be investigated.
Greenstar i Combi or System won’t reset
If your Greenstar i boiler will not reset, or the same fault keeps returning, don’t repeatedly reset it.
A reset can clear the immediate lockout condition but does not necessarily repair the underlying problem. Make a note of the complete fault code and contact a qualified engineer if the boiler remains in fault.
If your Worcester Greenstar i Combi or System boiler has stopped working and you need a boiler repair in Liverpool, Aigburth Plumbing & Heating can diagnose the fault and advise you on the appropriate repair.
Worcester Greenstar Heatslave error codes
The Worcester Bosch Greenstar Heatslave is an oil-fired boiler available in internal and external versions. Worcester Bosch has produced several generations of the Heatslave range, including the Greenstar Heatslave II, so the exact fault codes can vary depending on the boiler model and year of manufacture.
If your Greenstar Heatslave displays a fault, make a note of the complete fault code and cause code shown on the boiler. On some Heatslave models, a locking fault is displayed as an alphanumeric fault code together with a three-digit cause code.
Common Greenstar Heatslave fault codes
| Fault code | What it means |
|---|---|
| 9F | Burner lockout. |
| A7 | Domestic hot water temperature sensor fault. |
| A0 | Thermal store temperature sensor fault on applicable models. |
| EA | Fault associated with flame detection on applicable models. |
| E9 | Safety temperature limiter or overheating-related fault, depending on the model. |
The exact meaning of a code depends on the particular Heatslave model and its generation. Worcester Bosch provides separate manuals for the different Heatslave versions, including internal and external boilers.
Greenstar Heatslave 9F fault
A 9F fault indicates a burner lockout on applicable Greenstar Heatslave models.
A burner lockout can have several possible causes, including a problem with the oil supply or the burner itself. Worcester Bosch’s technical documentation advises checking the burner and fuel supply when this fault occurs.
If the boiler repeatedly goes into burner lockout, it should be diagnosed by a qualified heating engineer rather than repeatedly resetting the appliance.
Greenstar Heatslave A7 fault
An A7 fault indicates a problem with the domestic hot water temperature sensor on applicable Heatslave models.
If the fault remains after following the manufacturer’s reset procedure, the sensor and associated components will need to be checked by a qualified engineer.
Greenstar Heatslave won’t reset
Some Heatslave models allow the homeowner to press the reset button when the boiler enters a locking condition. If the reset is successful, the boiler should return to normal operation.
If the fault immediately returns after resetting, or the boiler repeatedly goes into lockout, don’t continue repeatedly resetting it. Make a note of the fault and cause codes and arrange for the boiler to be diagnosed.
Worcester Bosch’s user instructions explain that if a fault cannot be cleared using the reset control, further assistance is required.
If your Worcester Greenstar Heatslave has stopped working and you need a boiler repair in Liverpool, Aigburth Plumbing & Heating can diagnose the fault and advise you on the appropriate repair.
Worcester Greenstar Ri error codes
The Worcester Bosch Greenstar Ri is a regular boiler that has been available in several different versions over the years, including the Greenstar 9-24 Ri, 12-24 Ri and 27-30 Ri.
Because there are several generations of the Greenstar Ri, the way a fault is displayed can vary between models. Worcester Bosch provides separate operating and installation manuals for the different versions.
Unlike some newer Worcester boilers with a digital display, certain Greenstar Ri models indicate a fault using the flashing mains indicator light. The flashing sequence can help identify the fault. Worcester’s instructions advise giving the engineer the flashing sequence if the fault cannot be cleared.
Common Greenstar Ri boiler faults
| Fault | What it means |
|---|---|
| Boiler lockout | The boiler has detected a condition that has prevented it from operating safely. |
| Flashing mains indicator | The flashing sequence indicates that the boiler has detected a fault. |
| Ignition/flame failure | The boiler has been unable to establish or maintain a flame. |
| Overheating | The boiler has detected an excessive temperature condition and has shut down. |
| Fan or flue fault | The boiler has detected a problem affecting the fan or flue system on applicable models. |
| Sensor fault | A temperature sensor or associated wiring may have developed a fault. |
The exact fault and the way it is displayed depend on the particular Greenstar Ri model. If your boiler has a flashing indicator, note the flashing sequence before resetting it, as this can provide useful information to an engineer.
Greenstar Ri won’t reset
If your Greenstar Ri has gone into fault, the boiler can normally be reset using the thermostat/reset control. Worcester Bosch’s operating instructions explain that the control should be turned to the reset position and then returned to the required temperature setting.
If the boiler resets and operates normally, continue to monitor it. However, if the fault remains or the boiler repeatedly goes back into fault, don’t keep resetting it.
Make a note of the flashing light sequence and arrange for the boiler to be checked by a qualified Gas Safe registered engineer.
Greenstar Ri fault keeps coming back
A fault that repeatedly returns usually means that resetting the boiler has not resolved the underlying problem.
The cause could involve the ignition system, flame detection, fan, sensors, electrical controls or another part of the boiler or heating system. The exact cause needs to be diagnosed rather than simply resetting the appliance each time it stops working.
If your Worcester Greenstar Ri has stopped working and you need a boiler repair in Liverpool, Aigburth Plumbing & Heating can diagnose the fault and advise you on the appropriate repair.
Worcester GB162 error codes
The Worcester Bosch GB162 is a gas-fired condensing boiler available in higher-output models, including 50kW, 65kW, 80kW and 100kW versions. Worcester Bosch has produced different generations of the GB162, including the current GB162 V2, so the exact fault codes can vary between versions.
If your GB162 displays a fault, make a note of the complete fault code before resetting the boiler. Worcester Bosch provides separate operating and installation manuals for different generations of the GB162, so the correct manual should be used for the particular boiler.
Common Worcester GB162 fault conditions
GB162 boilers can display faults relating to areas such as:
- Low system pressure
- Temperature sensor faults
- Fan and air-flow problems
- Ignition and flame detection
- Gas valve faults
- Overheating
- Pump or water circulation
- Electronic control faults
The exact code and its meaning depend on the GB162 version and the complete code displayed.
Worcester GB162 won’t reset
If your GB162 has locked out, the boiler may be able to reset using its reset control, depending on the fault.
If the fault returns immediately after resetting, don’t repeatedly reset the boiler. Make a note of the complete fault code and arrange for the appliance to be diagnosed by a suitably qualified engineer.
Some GB162 faults require professional diagnosis because they can involve the combustion system, gas valve, fan, sensors or electronic controls.
Worcester GB162 fault keeps coming back
If the same fault repeatedly appears on your Worcester GB162, resetting the boiler is unlikely to resolve the underlying problem.
The fault could be caused by a component within the boiler or by an issue elsewhere in the heating system. A qualified engineer can use the displayed fault code together with the boiler’s fault history and operating conditions to establish the cause.
If your Worcester GB162 has developed a fault and you need a qualified boiler engineer in Liverpool, Aigburth Plumbing & Heating can diagnose the problem and advise you on the appropriate repair.
Worcester boiler has stopped working but shows no error code
Sometimes a Worcester Bosch boiler can stop firing or appear to stop working without displaying a conventional fault code.
Not every symbol or message displayed by a Worcester boiler means that the appliance has developed a fault. Some displays indicate normal operating conditions, such as the boiler filling the condensate trap, purging air from the system or temporarily limiting the temperature. These conditions can clear automatically.
Worcester boiler showing a symbol but no fault code
If your Worcester boiler is displaying a symbol rather than an error code, check the user manual for your particular model before assuming that the boiler has broken down.
For example, Worcester Bosch explains that some boilers can display a siphon-fill mode after the boiler has been switched off for a period of time. This is a normal safety function and should normally clear after around 15 minutes.
Other Worcester boilers can display an air-purge mode or a temperature-blocking condition. Again, these aren’t necessarily indications of a major boiler fault.
Worcester boiler stops but no error code is displayed
If your boiler has stopped providing heating or hot water and there is no obvious error code, check the basics first:
- Check that the boiler has power.
- Check that your heating controls or thermostat are calling for heat.
- Check the boiler pressure if your model has a pressure gauge or pressure display.
- Check whether the boiler is displaying a symbol or operating message.
- Check the manufacturer’s instructions for your particular model.
If the boiler still isn’t operating normally, there may be a fault that isn’t immediately obvious from the display.
When should I call an engineer?
If your Worcester boiler repeatedly stops working, fails to respond to the controls or continues to display an unusual symbol or message, it is best to have the problem investigated.
Don’t repeatedly reset the boiler if you cannot establish why it is stopping. Make a note of anything displayed on the boiler, as well as whether you have heating, hot water or neither.
A qualified Gas Safe registered engineer can diagnose the boiler and determine whether the problem is with the appliance, controls or heating system.
If your Worcester Bosch boiler has stopped working and you need a boiler repair in Liverpool, Aigburth Plumbing & Heating can diagnose the problem and advise you on the appropriate repair.
Worcester boiler maintenance and service mode
Some Worcester Bosch boilers have a service mode or maintenance menu that allows a qualified heating engineer to check and adjust the appliance during servicing.
The controls and procedure vary between Worcester boiler models. On some boilers, the service mode allows an engineer to run the boiler at maximum or minimum output and carry out combustion and performance checks. Worcester Bosch’s installation and servicing instructions specifically describe these functions as part of the servicing procedure.
Should I put my Worcester boiler into service mode?
If you’re a homeowner, you generally do not need to enter the service mode.
Service mode is intended for a qualified heating engineer carrying out checks on the boiler. Entering engineer settings without the correct equipment and knowledge can result in incorrect settings or an unsafe appliance.
If your Worcester boiler is displaying a maintenance message or service reminder, check the user manual for your particular model. Some Worcester boilers display maintenance codes separately from actual fault codes. For example, Worcester documentation describes codes beginning with H as maintenance indications rather than boiler faults.
Worcester boiler says it needs a service
If your Worcester boiler displays a service or maintenance reminder, it doesn’t necessarily mean the boiler has broken down.
It can simply indicate that the boiler is due for its scheduled service. Having the boiler serviced by a qualified Gas Safe registered engineer allows the appliance to be checked and maintained correctly.
If your Worcester boiler is showing an actual fault code as well as a service or maintenance message, make a note of the complete code before contacting an engineer.
If you need a Worcester boiler service or repair in Liverpool, Aigburth Plumbing & Heating can inspect the boiler and advise you on what is required.
What does the number on a Worcester boiler error code mean?
If your Worcester Bosch boiler is showing an error code with a number, make a note of the complete code, not just the letters.
For example, your boiler may display something such as:
- EA 227
- C6 215
- E2 222
- E9 276
The letters identify the general fault group, while the additional number can provide further information about the particular condition detected by the boiler. Worcester Bosch manuals describe these as cause codes on a number of Greenstar models.
Why is the full Worcester fault code important?
The same letters can be associated with different conditions depending on the Worcester boiler model and the complete code displayed.
For example, simply telling an engineer that your boiler is showing EA gives less information than providing the complete code, such as EA 227.
When contacting a boiler engineer, try to provide:
- The complete fault code
- The Worcester boiler model
- Whether you have heating and hot water
- Whether the boiler has been reset
- Whether the same fault keeps returning
This information can help the engineer understand the problem before attending.
Where can I find my Worcester boiler fault code?
The way a fault is displayed depends on the Worcester Bosch model.
Newer boilers may show the fault code and cause code directly on the digital display. Older Greenstar boilers can use different displays or flashing indicator lights to communicate a fault.
Worcester Bosch provides model-specific user manuals, so if you’re unsure what a particular code means, check the manual for your exact boiler.
If your Worcester boiler is displaying a fault that you don’t recognise, make a note of the entire code before resetting it. If the fault returns after resetting, the underlying problem will need to be diagnosed by a qualified Gas Safe registered engineer.
Worcester boiler fault – what should I do?
If your Worcester Bosch boiler has developed a fault, the first thing to do is make a note of the complete error code or flashing light sequence.
The fault code can give an engineer useful information about what the boiler has detected. However, an error code does not always identify the exact component that has failed. Further diagnosis may be required to establish the underlying cause.
My Worcester boiler has a fault
If your Worcester boiler has stopped working:
- Make a note of the complete fault code.
- Check the boiler pressure if your model has a pressure gauge or pressure display.
- Check that the boiler has power.
- Check that your heating controls are switched on and calling for heat.
- Follow the manufacturer’s instructions for resetting your particular model.
- If the fault returns, arrange for the boiler to be checked by a qualified engineer.
Don’t repeatedly reset the boiler if the same fault keeps returning. A reset can clear a lockout condition, but it does not necessarily fix the underlying problem.
Worcester Bosch also provides an online troubleshooting tool and model-specific manuals for homeowners.
Does a Worcester fault code tell you what part has failed?
Not necessarily.
A fault code can indicate the area of the boiler where a problem has been detected, but several different causes can produce the same code. For example, an EA fault indicates that the boiler has failed to detect a flame, but the reason for this can involve different parts of the appliance or heating system.
This is why replacing a component simply because an error code has appeared is not always the correct solution.
A qualified Gas Safe registered engineer can carry out the appropriate checks and establish what has caused the boiler to go into fault.
Worcester boiler fault in Liverpool
If your Worcester Bosch boiler has developed a fault, Aigburth Plumbing & Heating can diagnose Worcester boiler problems and carry out repairs throughout Liverpool.
When contacting us, it is helpful to provide the Worcester boiler model and complete error code, if one is displayed. This allows us to have as much information as possible before attending.
Worcester A21 error code
The meaning of a Worcester A21 error code depends on the particular Worcester Bosch appliance and control system.
Unlike codes such as EA 227, which are commonly associated with a boiler ignition/flame fault, A21 can be used for different conditions on different Worcester equipment.
For example, Worcester documentation for some heating systems uses A21 for a communication or configuration issue involving the heating circuit controller. On certain Worcester wireless controls, A21 can instead indicate a problem establishing or maintaining the radio-frequency connection between the thermostat and receiver.
What should I do if my Worcester boiler shows A21?
If your Worcester boiler or heating control displays A21, make a note of:
- The complete code, including any numbers displayed with it
- The exact Worcester boiler model
- Whether the code is displayed on the boiler or a heating control/thermostat
- Whether you still have heating and hot water
Don’t assume that A21 means a particular boiler component has failed. The correct diagnosis depends on the appliance and controls installed.
If A21 remains displayed or your heating isn’t operating correctly, check the user manual for your specific Worcester system or arrange for a qualified engineer to investigate the problem.
If your Worcester heating system is showing an A21 fault and you need help in Liverpool, Aigburth Plumbing & Heating can diagnose the problem and advise you on the appropriate repair.
Worcester EA 227 error code
EA 227 is one of the most commonly recognised fault codes on Worcester Bosch boilers.
The EA indicates that the boiler has failed to establish or detect a flame, while 227 is the associated three-digit cause code on models that use this display format. Worcester Bosch’s manuals specifically show EA 227 as an example of a boiler alert and recommend quoting both the fault code and three-digit number when seeking assistance.
What causes a Worcester EA 227 fault?
There isn’t one single cause of an EA 227 fault. Possible causes can include:
- A problem with the gas supply
- An ignition problem
- A flame detection problem
- A blocked or frozen condensate pipe
- A problem with the flue
- Another boiler component preventing the burner from operating correctly
A blocked or frozen condensate pipe is particularly worth considering during very cold weather. Worcester Bosch states that a boiler may repeatedly lock out and display an EA code when the condensate pipe is blocked, often accompanied by a gurgling noise when the boiler attempts to start.
Can I reset an EA 227 fault?
You can follow the reset procedure in the user manual for your particular Worcester boiler.
Worcester Bosch’s manuals show that if a reset is successful, the boiler should return to normal operation. If the reset is unsuccessful, the fault code will be displayed again. Some fault conditions cannot be cleared by a simple reset and require an engineer.
If EA 227 keeps coming back, don’t repeatedly reset the boiler. The underlying cause needs to be diagnosed.
Worcester EA 227 in cold weather
If your Worcester boiler develops an EA 227 fault during freezing weather, check whether the condensate pipe runs outside the property.
If the pipe is frozen and is at ground level and safely accessible, Worcester Bosch recommends thawing it using warm water. Do not use boiling water, as this can damage the pipe.
If the fault remains after the condensate pipe has been safely thawed and the boiler reset according to the manufacturer’s instructions, the problem may have another cause and should be investigated by a qualified engineer.
Need a Worcester EA 227 repair in Liverpool?
If your Worcester Bosch boiler is displaying EA 227 and the fault keeps returning, Aigburth Plumbing & Heating can diagnose the problem and carry out the necessary boiler repair in Liverpool.
When contacting an engineer, provide the complete fault code — EA 227 — along with the Worcester boiler model. This gives the engineer useful information before attending.
Worcester C6 error code
A C6 error code on a Worcester Bosch boiler is generally associated with a fan or airflow problem.
The exact meaning depends on the Worcester boiler model and the additional cause code displayed. For example, Worcester documentation shows C6 215 as a fan running too fast and C6 216 as a fan running too slowly on some Greenstar models.
What causes a Worcester C6 fault?
Possible causes can include:
- A problem with the boiler fan
- An electrical or wiring problem involving the fan
- An airflow or flue-related problem
- A problem with the boiler’s electronic controls
The C6 code therefore doesn’t automatically mean that the fan itself needs replacing. The boiler needs to be diagnosed to establish the actual cause.
Can I reset a Worcester C6 fault?
Depending on the Worcester model, C6 may be a locking fault that can be reset using the boiler’s reset control.
If the boiler returns to normal operation after a reset, monitor it. If the C6 fault comes back, don’t repeatedly reset the boiler. The underlying problem needs to be investigated by a qualified engineer.
The boiler fan is part of the appliance’s combustion and flue system, so internal repairs should only be carried out by a suitably qualified Gas Safe registered engineer.
Worcester C6 fault in Liverpool
If your Worcester Bosch boiler is displaying C6, make a note of the complete code, including any number displayed alongside it.
Aigburth Plumbing & Heating can diagnose Worcester boiler faults and carry out boiler repairs throughout Liverpool.
Worcester E9 error code
The E9 error code on a Worcester Bosch boiler generally indicates that a safety temperature limiter has operated or that the boiler has detected an overheating-related condition.
The exact meaning can vary between Worcester boiler models. For example, Worcester documentation describes E9 as the safety temperature limiter operating on some Greenstar boilers, while other models use E9 for conditions such as the flow or safety sensor temperature becoming too high.
What causes a Worcester E9 fault?
Possible causes can include:
- Poor water circulation
- A problem with the boiler pump
- Low system pressure
- A temperature sensor or safety limiter problem
- An overheating condition
- Air or another circulation problem within the heating system
An E9 code therefore doesn’t automatically mean that one particular component needs replacing. The boiler needs to be diagnosed to establish why the safety system has operated.
Can I reset a Worcester E9 fault?
You can follow the reset procedure in the user manual for your particular Worcester boiler.
If the boiler returns to normal operation after a reset, monitor it. However, if E9 keeps returning, don’t repeatedly reset the boiler. The underlying cause needs to be investigated.
Worcester Bosch’s own fault-finding information identifies E9 as a condition requiring checks of areas such as system pressure, safety temperature devices and pump operation on applicable models.
Worcester E9 fault keeps coming back
If your Worcester boiler repeatedly displays E9, there is likely to be an underlying problem causing the boiler to shut down for safety.
Make a note of the complete fault code and your Worcester boiler model before contacting an engineer. This helps ensure the correct fault information is used for your particular appliance.
If your Worcester boiler is displaying an E9 fault and you need a boiler repair in Liverpool, Aigburth Plumbing & Heating can diagnose the problem and advise you on the appropriate repair.
Worcester F0 error code
The F0 error code on a Worcester Bosch boiler generally indicates an internal boiler fault.
Worcester Bosch uses F0 to identify an internal error on a number of its Greenstar boilers. The exact cause can vary depending on the boiler model and the complete code displayed.
What causes a Worcester F0 fault?
An F0 fault can be associated with an electrical or electronic problem within the boiler. Possible causes can include:
- An electrical connection fault
- A problem with the boiler’s electronic control system
- A fault affecting the ignition or control circuitry
- Another internal boiler problem
The F0 code does not necessarily identify the exact component that has failed. Further diagnosis is normally required.
Can I reset a Worcester F0 fault?
You can follow the reset instructions for your particular Worcester boiler.
If the F0 fault clears and the boiler operates normally, monitor it. However, if F0 returns after resetting, don’t repeatedly reset the boiler. The underlying fault needs to be investigated.
Worcester Bosch’s own documentation advises homeowners not to attempt to rectify listed fault conditions themselves and to contact a competent, qualified engineer.
Worcester F0 fault in Liverpool
If your Worcester Bosch boiler is displaying F0, make a note of the complete code and the boiler model before contacting an engineer.
Worcester F7 and FA error codes
The F7 and FA error codes on Worcester Bosch boilers are both associated with the boiler detecting a flame signal when it should not be present.
The exact cause depends on the Worcester boiler model, but both codes require the boiler to be properly diagnosed if they persist or keep returning.
Worcester F7 error code
A F7 fault generally means that the boiler has detected a flame signal even though the appliance is switched off.
Worcester Bosch lists F7 as “flame detected even though boiler switched off” on a number of its Greenstar boilers.
There can be several possible causes, so the F7 code does not automatically mean that one particular component needs replacing. The boiler’s flame detection system and associated components may need to be checked by a qualified engineer.
Worcester FA error code
An FA fault generally means that the boiler has detected a flame signal after the gas supply to the burner has been shut off.
Worcester Bosch lists FA as “flame detected after gas shut off” on several Greenstar models.
Because this involves the boiler’s flame detection and gas-control systems, the cause needs to be diagnosed rather than attempting to repair the boiler yourself.
Can I reset a Worcester F7 or FA fault?
You can follow the reset procedure in the user manual for your particular Worcester Bosch boiler.
If the boiler resets and operates normally, monitor it. However, if F7 or FA returns, don’t repeatedly reset the boiler. The underlying cause needs to be investigated by a qualified Gas Safe registered engineer.
If your Worcester boiler is displaying F7 or FA, make a note of the complete fault code and the boiler model before contacting an engineer.
If you need a Worcester boiler repair in Liverpool, Aigburth Plumbing & Heating can diagnose the fault and advise on the appropriate repair.
Other common Worcester Bosch error codes
There are a number of other Worcester Bosch error codes that you may come across. The exact meaning can depend on the boiler model, so always check the complete code against the manual for your particular appliance.
Worcester E2 error code
An E2 error code generally indicates a problem with the central-heating flow temperature sensor.
Worcester Bosch describes E2 as a defective CH flow NTC sensor on a number of its Greenstar boilers. The sensor monitors the temperature of the water leaving the boiler and helps the appliance control its operation safely.
Possible causes can include:
- A faulty temperature sensor
- A wiring or electrical connection problem
- A problem with the boiler’s control system
If an E2 fault remains after resetting the boiler, or keeps returning, it will need to be diagnosed by a qualified engineer.
Worcester Fd error code
An Fd or FD error code can indicate that the reset button has been pressed by mistake.
Worcester Bosch lists Fd as “reset button pressed by mistake” on a number of Greenstar models. On applicable boilers, pressing the reset control again can clear the condition.
If the Fd code clears and the boiler operates normally, no further action may be required. However, if another fault appears or the boiler continues to stop working, the underlying problem may need to be investigated.
Worcester A1 error code
The meaning of an A1 error code depends on the particular Worcester Bosch boiler model.
On some older Greenstar boilers, A1 is associated with a pump or water-circulation problem, while other Worcester appliances can use A1 differently. This is why it is important not to assume that every A1 code has exactly the same meaning.
If your Worcester boiler displays A1, make a note of the complete code and boiler model and check the appropriate Worcester Bosch manual.
If the fault remains or your heating and hot water are affected, a qualified Gas Safe registered engineer can diagnose the cause.
Other Worcester Bosch codes
Worcester Bosch boilers can display many other codes relating to areas such as:
- Temperature sensors
- Boiler pressure
- Pumps and water circulation
- Fans and airflow
- Ignition and flame detection
- Gas valves
- Electrical controls
- Communication between boiler components
- Condensate systems
- Maintenance requirements
Because Worcester has produced many different boiler models over the years, the same letters or numbers should not automatically be assumed to have the same meaning on every appliance.
If you cannot find your particular Worcester error code above, make a note of the complete code, boiler model and any additional numbers displayed. This information will help a qualified engineer identify the correct fault information for your boiler.
If your Worcester Bosch boiler has developed a fault and you need a boiler repair in Liverpool, Aigburth Plumbing & Heating can diagnose the problem and advise on the appropriate repair.
Worcester boiler error code tables
Below you’ll find fault-code information for a range of Worcester Bosch boilers, including the Greenstar 8000, Greenstar 4000, CDi, Greenstar i, Greenstar Ri, Greenstar Heatslave and GB162.
Because Worcester Bosch has produced many different boiler models and versions over the years, the meaning of a particular code can vary between appliances. Worcester provides separate manuals for different models and production periods, so it is important to check the information against your exact boiler.
How to find your Worcester boiler error code
Before looking at the tables, make a note of:
- Your Worcester boiler model
- The complete error code
- Any additional numbers displayed
- Whether you have heating and hot water
- Whether the boiler has been reset already
For example, EA 227 provides more information than simply saying the boiler is displaying EA.
Find your Worcester boiler model below and then look for the complete fault code in the relevant table.
If you cannot find your code, don’t assume that a similar-looking code from another Worcester boiler has the same meaning. Check the correct Worcester Bosch manual or contact a qualified Gas Safe registered engineer.
Worcester Bosch boiler manuals
Worcester boiler error codes – frequently asked questions
What is the most common Worcester boiler error code?
EA is one of the most commonly encountered Worcester Bosch fault codes. It generally indicates that the boiler has failed to establish or detect a flame. The exact cause depends on the boiler model and complete code displayed.
What does EA 227 mean on a Worcester boiler?
EA 227 indicates that the boiler has failed to detect a flame after attempting ignition. Possible causes include problems with the gas supply, ignition, flame detection, condensate system or other boiler components.
What does C6 mean on a Worcester boiler?
A C6 fault is generally associated with the boiler fan or its operation. The additional number displayed can provide more information about the particular fault.
What does E9 mean on a Worcester boiler?
An E9 fault generally indicates that a safety temperature limiter has operated or that the boiler has detected an overheating-related condition. The exact meaning depends on the Worcester model.
Why does my Worcester boiler keep showing an error code?
If the same error code keeps returning after the boiler has been reset, there is likely to be an underlying problem that has not been resolved. Repeatedly resetting the boiler is not a substitute for diagnosing the fault.
Can I reset my Worcester boiler myself?
In many cases, a homeowner can use the boiler’s reset control in accordance with the manufacturer’s instructions. However, if the fault returns or the boiler will not reset, the cause should be investigated by a qualified engineer.
Why has my Worcester boiler stopped working with no error code?
Not every message or symbol displayed by a Worcester boiler indicates a fault. Some displays indicate normal operating conditions or temporary operating modes. If the boiler has stopped providing heating or hot water without showing a conventional error code, check the power, heating controls and boiler pressure where applicable, then consult the manual for your particular model.
Where can I find the error code on my Worcester boiler?
The location and way the code is displayed depends on the Worcester Bosch model. Newer boilers normally show the information on a digital display, while some older models use indicator lights or different displays.
Make a note of the complete code, including any numbers shown alongside the letters.
Does a Worcester boiler error code tell me which part needs replacing?
Not necessarily. An error code identifies a condition detected by the boiler but does not always identify the exact component that has failed. Proper diagnosis is often required before a part is replaced.
Who can repair a Worcester boiler in Liverpool?
A Worcester Bosch boiler fault should be diagnosed and repaired by a suitably qualified Gas Safe registered engineer. Aigburth Plumbing & Heating provides Worcester boiler fault diagnosis and repairs throughout Liverpool.
For the correct information for your particular boiler, Worcester Bosch also provides model-specific user manuals and troubleshooting resources.