BoilerFaultCodes -ll-
Your boiler is performing a routine internal safety check to ensure internal water levels are correct and will return to normal operation automatically within 15 minutes.
Worcester Bosch R30 HE Plus Fault codes & diagnostics
27 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
System Natural Gas 35-40 kW 2006-2012 Discontinued
Replaced by: Greenstar i System
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Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →
Severity at a glance
Each cell = one fault code. Hover to identify. 2 Emergency
15 High
1 Medium
9 Low
Just want the most common Worcester Bosch R30 HE Plus faults?
The top 6 problems in plain English — with causes, DIY checks and repair costs.
Fault codes
All 27 documented codes
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−II− Your boiler is currently running a 15-minute cleaning and safety cycle to fill up its internal drainage system, which is a normal process after a power cut or reset.
Your boiler is currently running a 15-minute cleaning and safety cycle to fill up its internal drainage system, which is a normal process after a power cut or reset.
What to check first
- Wait for 15 minutes for the timer to finish
- Ensure any thermostat or timer is calling for heat
- Monitor the display to see if it returns to a normal temperature reading
0.0 Your boiler has logged a previous historical error message, but it does not necessarily mean the appliance is currently broken.
Your boiler has logged a previous historical error message, but it does not necessarily mean the appliance is currently broken.
Parts commonly replaced
- Not applicable
Related codes
3.9 Your boiler has detected an internal communication error and has safely shut itself down to prevent further damage.
Your boiler has detected an internal communication error and has safely shut itself down to prevent further damage.
Parts commonly replaced
- Printed Circuit Board (PCB)
- Wiring harness
Related codes
4.7 Your boiler is providing an informational status notification rather than indicating a system fault, so your heating and hot water should continue to operate normally.
Your boiler is providing an informational status notification rather than indicating a system fault, so your heating and hot water should continue to operate normally.
Parts commonly replaced
- NTC Temperature Sensor
- System Pump
10 Your boiler has detected a serious internal system error that prevents it from firing up and providing heating or hot water.
Your boiler has detected a serious internal system error that prevents it from firing up and providing heating or hot water.
Parts commonly replaced
- Printed Circuit Board (PCB)
- Wiring Harness
- Ignition Transformer
Related codes
A1 Your boiler has detected that the water pump is stuck or not moving water properly, which could cause the system to overheat.
Your boiler has detected that the water pump is stuck or not moving water properly, which could cause the system to overheat.
Parts commonly replaced
- Central heating pump
- Pump capacitor
- Circuit board
Related codes
A7 Your boiler is struggling to accurately measure the temperature of the water used for your taps and shower, meaning it will likely stop producing hot water to prevent overheating.
Your boiler is struggling to accurately measure the temperature of the water used for your taps and shower, meaning it will likely stop producing hot water to prevent overheating.
Parts commonly replaced
- Domestic Hot Water NTC sensor
Related codes
A8 Your boiler's electronic parts have lost their connection with each other, meaning the system cannot run as it no longer knows how to control its internal components.
Your boiler's electronic parts have lost their connection with each other, meaning the system cannot run as it no longer knows how to control its internal components.
Parts commonly replaced
- Printed Circuit Board (PCB)
- Wiring harness
Related codes
b1 Your boiler's internal computer is failing to communicate with a small identity chip that holds its configuration settings, meaning it cannot operate safely.
Your boiler's internal computer is failing to communicate with a small identity chip that holds its configuration settings, meaning it cannot operate safely.
Parts commonly replaced
- Code plug
- Printed Circuit Board (PCB)
Related codes
Showing 11–20 of 27
C1 Your boiler has detected that the internal fan is moving too slowly to safely clear exhaust gases, so it has stopped working to keep your home safe.
Your boiler has detected that the internal fan is moving too slowly to safely clear exhaust gases, so it has stopped working to keep your home safe.
Parts commonly replaced
- Fan assembly
- Printed Circuit Board (PCB)
Related codes
C4 Your boiler's internal fan is stuck running continuously, which prevents the system from starting its normal cycle and will eventually cause further components to fail.
Your boiler's internal fan is stuck running continuously, which prevents the system from starting its normal cycle and will eventually cause further components to fail.
Parts commonly replaced
- Fan assembly
- Printed circuit board (PCB)
Related codes
C6 Your boiler has detected that the internal fan is spinning faster than it should, so it has safely shut itself down to prevent damage.
Your boiler has detected that the internal fan is spinning faster than it should, so it has safely shut itself down to prevent damage.
Parts commonly replaced
- Fan assembly
- Printed Circuit Board (PCB)
Related codes
d3 Your boiler has stopped working because a safety link inside the unit has either come loose or a connected external safety device has shut the system down.
Your boiler has stopped working because a safety link inside the unit has either come loose or a connected external safety device has shut the system down.
Parts commonly replaced
- Link plug
- External overheat thermostat
- Wiring harness
Related codes
E2 Your boiler has stopped working because a sensor that measures the water temperature is broken or has a faulty connection.
Your boiler has stopped working because a sensor that measures the water temperature is broken or has a faulty connection.
Parts commonly replaced
- NTC Temperature Sensor
- Wiring Harness
Related codes
E9 Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Parts commonly replaced
- High limit thermostat
- Heat exchanger temperature sensor
- Central heating pump
- System filter
Related codes
EA Your boiler is failing to light the internal flame needed to heat your water and home.
Your boiler is failing to light the internal flame needed to heat your water and home.
Parts commonly replaced
- Ignition electrode
- Gas valve
- Flame rectification probe
Related codes
F0 Your boiler's computer is experiencing a general internal failure and cannot safely continue to run.
Your boiler's computer is experiencing a general internal failure and cannot safely continue to run.
Parts commonly replaced
- Printed Circuit Board (PCB)
- Wiring harness
Related codes
F7 Your boiler has detected a flame inside the unit despite the system thinking it is turned off, which prevents it from operating safely.
Your boiler has detected a flame inside the unit despite the system thinking it is turned off, which prevents it from operating safely.
Parts commonly replaced
- Gas valve
- Printed Circuit Board (PCB)
- Ionisation probe
Related codes
FA Your boiler has detected a flame even though it has commanded the gas supply to stop, which indicates a serious safety issue that requires urgent attention.
Your boiler has detected a flame even though it has commanded the gas supply to stop, which indicates a serious safety issue that requires urgent attention.
Parts commonly replaced
- Gas valve
- Printed Circuit Board (PCB)
- Flame detection electrode
Related codes
Showing 21–27 of 27
FC Your boiler's control panel has lost its connection to the main brain of the heating system, preventing it from displaying information or responding to commands.
Your boiler's control panel has lost its connection to the main brain of the heating system, preventing it from displaying information or responding to commands.
Parts commonly replaced
- User Interface Module
- Main Control PCB
- Wiring harness
Related codes
Fd Your boiler's reset button has been held down for too long, causing the control panel to enter a locked state.
Your boiler's reset button has been held down for too long, causing the control panel to enter a locked state.
What to check first
- Switch the boiler off at the fused spur or mains power supply
- Wait for 60 seconds to allow the internal electronics to discharge
- Switch the power back on and, if the boiler does not automatically resume, press the reset button once firmly and release immediately
P1 Your boiler is undergoing a startup sequence or a temporary software update and needs time to finish its internal checks.
Your boiler is undergoing a startup sequence or a temporary software update and needs time to finish its internal checks.
What to check first
- Wait for 5-10 minutes for the sequence to complete
- Observe if the display changes to a temperature or status code
- Only contact an engineer if the code persists for more than 30 minutes
Parts commonly replaced
- PCB (Control Board)
- Display Interface
P1, P2, P3, P1...
Your boiler is simply performing a routine internal check as it starts up, so there is no need to worry as it will clear itself automatically.
P2 Your boiler is undergoing a startup sequence or a temporary software update and needs time to finish its internal checks.
Your boiler is undergoing a startup sequence or a temporary software update and needs time to finish its internal checks.
What to check first
- Wait up to 15 minutes for the sequence to complete
- Do not turn the power off during the update
- If the code persists for over an hour, try a single reset
Parts commonly replaced
- PCB (Control Board)
- Display Interface
P3 Your boiler is undergoing a startup sequence or a temporary software update and needs time to finish its internal checks.
Your boiler is undergoing a startup sequence or a temporary software update and needs time to finish its internal checks.
What to check first
- Wait for 5-10 minutes for the sequence to complete
- Monitor the display to see if it transitions to a normal temperature reading
- If the code persists for over 15 minutes, try a single reset of the boiler
Parts commonly replaced
- PCB (Control Board)
- Display Interface
P4 Your boiler is undergoing a startup sequence or a temporary software update and needs time to finish its internal checks.
Your boiler is undergoing a startup sequence or a temporary software update and needs time to finish its internal checks.
What to check first
- Wait up to 15 minutes for the sequence to complete
- Do not turn the power off during the update
- Observe the display to see if it reverts to a normal temperature reading
Parts commonly replaced
- PCB (Control Board)
- Display Interface