BoilerFaultCodes 2.4
Your boiler is simply taking a short, programmed break to prevent excessive wear and tear before it restarts your heating.
Worcester Bosch Ri 25 HE Fault codes & diagnostics
19 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Regular Natural Gas 25 kW 2006-2012 Discontinued
Replaced by: Greenstar i Regular
No manual available yet
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Severity at a glance
Each cell = one fault code. Hover to identify. 2 Emergency
15 High
2 Low
Just want the most common Worcester Bosch Ri 25 HE faults?
The top 6 problems in plain English — with causes, DIY checks and repair costs.
Fault codes
All 19 documented codes
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5.2 Your boiler's main control computer is struggling to communicate or process information correctly, which has caused it to stop heating your home as a safety precaution.
Your boiler's main control computer is struggling to communicate or process information correctly, which has caused it to stop heating your home as a safety precaution.
Parts commonly replaced
- Gas Fire Assembly (GFA) unit
- Printed Circuit Board (PCB)
Related codes
9.3 Your boiler has detected an internal computer error that prevents it from starting up correctly.
Your boiler has detected an internal computer error that prevents it from starting up correctly.
Parts commonly replaced
- Gas Fire Automator (GFA)
- Main PCB
A7 Your boiler is struggling to accurately detect the temperature of the water being used, which will likely prevent you from having hot water until it is fixed.
Your boiler is struggling to accurately detect the temperature of the water being used, which will likely prevent you from having hot water until it is fixed.
Parts commonly replaced
- NTC Temperature Sensor
Related codes
AC Your boiler's internal computer is unable to communicate with its control panel, meaning the unit cannot safely start or regulate your heating and hot water.
Your boiler's internal computer is unable to communicate with its control panel, meaning the unit cannot safely start or regulate your heating and hot water.
Parts commonly replaced
- Main electronic control board
- Wiring harness
Related codes
Ad Your boiler has detected that the water temperature has risen too quickly, leading it to shut down for safety to prevent overheating.
Your boiler has detected that the water temperature has risen too quickly, leading it to shut down for safety to prevent overheating.
Parts commonly replaced
- NTC Sensor
- Heat Exchanger
- Pump
Related codes
b1 Your boiler's internal control unit is struggling to recognise a crucial electrical connection, which is preventing the system from starting up.
Your boiler's internal control unit is struggling to recognise a crucial electrical connection, which is preventing the system from starting up.
Parts commonly replaced
- Keyed plug
- PCB (Printed Circuit Board)
- Wiring harness
Related codes
C1 Your boiler is struggling to push air through the system to burn fuel safely, so it has stopped working to protect itself.
Your boiler is struggling to push air through the system to burn fuel safely, so it has stopped working to protect itself.
Parts commonly replaced
- Fan assembly
- Air pressure switch
- Wiring harness
- Printed Circuit Board
Related codes
C6 Your boiler has detected that the internal fan responsible for moving air and burnt gases is spinning faster than it should, causing the system to stop working for safety reasons.
Your boiler has detected that the internal fan responsible for moving air and burnt gases is spinning faster than it should, causing the system to stop working for safety reasons.
Parts commonly replaced
- Fan assembly
- Printed Circuit Board (PCB)
Related codes
d3 Your boiler has lost the signal that tells it to turn on, likely due to a loose wire or a disconnected control link inside the unit.
Your boiler has lost the signal that tells it to turn on, likely due to a loose wire or a disconnected control link inside the unit.
Parts commonly replaced
- Control board
- Wiring harness
- External thermostat/programmer link
Related codes
E2 Your boiler has lost the ability to accurately measure the temperature of the water flowing through it, so it has shut down as a precaution to prevent overheating.
Your boiler has lost the ability to accurately measure the temperature of the water flowing through it, so it has shut down as a precaution to prevent overheating.
Parts commonly replaced
- NTC Temperature Sensor
- Wiring Harness
Related codes
E9 Your boiler has detected that it is dangerously overheating and has automatically shut itself down to prevent internal damage.
Your boiler has detected that it is dangerously overheating and has automatically shut itself down to prevent internal damage.
Parts commonly replaced
- Pump
- NTC thermistor
- Primary heat exchanger
- PCB
Related codes
EA Your boiler is failing to light the internal flame, which means it cannot provide you with any heating or hot water.
Your boiler is failing to light the internal flame, which means it cannot provide you with any heating or hot water.
Parts commonly replaced
- Ignition electrode
- Gas valve
- Printed Circuit Board
Related codes
F7 Your boiler is detects a flame when it should be turned off, which is a safety concern that requires an immediate professional inspection.
Your boiler is detects a flame when it should be turned off, which is a safety concern that requires an immediate professional inspection.
Parts commonly replaced
- Gas valve
- Printed Circuit Board (PCB)
- Flame detection electrode
Related codes
FA Your boiler has detected that a flame is still burning inside even though it has commanded the gas supply to turn off, which is a potential safety concern.
Your boiler has detected that a flame is still burning inside even though it has commanded the gas supply to turn off, which is a potential safety concern.
Parts commonly replaced
- Gas valve
- Printed Circuit Board (PCB)
- Flame rectification electrode
Related codes
Fd Your boiler has entered a temporary safety mode because the reset button was held down for too long, essentially causing a software lock.
Your boiler has entered a temporary safety mode because the reset button was held down for too long, essentially causing a software lock.
What to check first
- Switch the boiler off at the fused spur or mains power supply.
- Wait for 60 seconds to allow the internal memory to reset.
- Switch the power back on and, if necessary, press the reset button once briefly.
P1 Your boiler is currently unable to start because a small protective fuse inside the control unit has failed, preventing the system from powering up.
Your boiler is currently unable to start because a small protective fuse inside the control unit has failed, preventing the system from powering up.
Parts commonly replaced
- 1.6A T fuse
- Control board
Related codes
P2 Your boiler is currently unable to start up because a small internal safety fuse has blown, preventing the electrical system from powering on.
Your boiler is currently unable to start up because a small internal safety fuse has blown, preventing the electrical system from powering on.
Parts commonly replaced
- Control board fuse
- Main control unit
Related codes
P3 Your boiler is currently unable to start its control systems because a small internal protective fuse has failed and needs to be swapped for a new one.
Your boiler is currently unable to start its control systems because a small internal protective fuse has failed and needs to be swapped for a new one.
Parts commonly replaced
- Internal 24V fuse
- Main printed circuit board (PCB)
Related codes
Status & diagnostic codes 5 operating states & engineer diagnostics
Not faults — these are normal operating states. Tap to expand.
5 operating states & engineer diagnostics
Not faults — these are normal operating states. Tap to expand.
0.0 Status Your boiler is currently operating normally and does not have an active fault; if there was a previous issue, this code is simply showing it has been resolved. 2.5 Diagnostic Your boiler has detected that the water inside the unit is getting too hot and has automatically shut down to prevent damage. 2.6 Diagnostic Your boiler is struggling to control exactly how much heat it produces, causing it to cycle on and off more frequently than it should. 5.0 Diagnostic Your boiler is currently operating at its maximum heating capacity and is functioning normally, rather than indicating a fault. 6.8 Diagnostic Your boiler is struggling to reach or maintain the correct temperature because it has been running in its hot water cycle for too long, suggesting it cannot satisfy the thermostat's demand.