Worcester Bosch
Greenstar 8000 Life 50kW
Combi Boiler
50kW
2019-present
ErP A
80 fault codes
<p>The Greenstar 8000 Life 50kW is a combi boiler from Worcester Bosch, available at 50kW output. Produced 2019-present.</p>
Greenstar 8000 Life 50kW Fault Codes 80
Code
Description
Severity
Type
1017 W
Low Water Pressure Warning (8000 Series)
On Worcester Greenstar 8000 boilers, code 1017 W indicates the system water pressure is too low.…
Low
DIY
View Guide
1065 B
Pressure Sensor Defective (8000 Series)
On 8000 Series boilers, code 1065 B indicates the pressure sensor is not connected or has…
Medium
Engineer
View Guide
1073 W
Flow Temperature Sensor Short Circuit (8000 Series)
On 8000 Series boilers, code 1073 W indicates a short circuit in the flow temperature sensor.
Medium
Engineer
View Guide
1074 W
Flow Temperature Sensor No Signal (8000 Series)
On 8000 Series boilers, code 1074 W means the flow temperature sensor is not providing a…
Medium
Engineer
View Guide
224 V
Safety Temperature Limiter Tripped (8000 Series)
On 8000 Series boilers, code 224 V means the safety temperature limiter has operated. 'V' indicates…
High
Engineer
View Guide
227
Ignition Lockout (Older CDi Models)
On older Worcester Greenstar CDi models, fault code 227 indicates ignition failure after multiple attempts.
Medium
DIY
View Guide
227 V
No Flame Signal (8000 Series Lockout)
On 8000 Series boilers, code 227 V is a lockout (V = lockout) for no flame…
Medium
DIY
View Guide
2927 B
Flame Lost During Operation (8000 Series)
On 8000 Series boilers, code 2927 B means the ionisation current was insufficient during the burning…
Medium
DIY
View Guide
2948 B
No Flame Signal (8000 Series)
On Greenstar 8000 boilers, code 2948 B indicates no flame signal was detected. At low output…
Medium
Engineer
View Guide
2965 B
Flow Temperature Too High (8000 Series)
On 8000 Series boilers, code 2965 B means the flow temperature has exceeded safe limits.
High
Engineer
View Guide
2965 V
Flue Gas Sensor Short Circuit
The flue gas NTC has a short circuit.
Medium
Engineer
View Guide
2970 B
System Pressure Drop Too Rapid (8000 Series)
On 8000 Series boilers, code 2970 B means system pressure is dropping at an unusually rapid…
High
Engineer
View Guide
2971 B
System Pressure Too Low (8000 Series)
On 8000 Series boilers, code 2971 B indicates system pressure is below the minimum. The boiler…
Low
DIY
View Guide
360 V
Incompatible Code Plug (8000 Series)
On 8000 Series boilers, code 360 V means the code plug (boiler identification module) is not…
Medium
Engineer
View Guide
6A
Safety Fuse Fault
The internal safety fuse has blown. This can be caused by tampering, poor maintenance, or loose…
High
Engineer
View Guide
9U
Blocked Condensate / Condense Sensor
The condensate system is blocked or the condensate sensor is indicating a problem. Most commonly caused…
Medium
DIY
View Guide
9U 257
Appliance Variant Not Set
The boiler variant has not been correctly configured.
High
Engineer
View Guide
A1
Pump Stuck or Running Dry
The circulation pump is not running correctly — either it is seized, running without water, or…
High
Engineer
View Guide
A21
Thermostat / Receiver Communication Fault
The boiler cannot communicate with the wireless thermostat receiver. Usually caused by low batteries in the…
Low
DIY
View Guide
A21 281
Pump Blockage / Circulation Fault
The pump is blocked, preventing proper water circulation through the system.
High
Engineer
View Guide
A22
Loss of RF Signal
The boiler has lost the wireless radio frequency signal from the room thermostat. The thermostat may…
Low
DIY
View Guide
A281
Internal Water Leak Detected
The boiler has detected an internal water leak. Water may be dripping onto internal components which…
High
Engineer
View Guide
A61
Gas Valve Fault
There is a fault with the gas valve — it may not be opening or closing…
High
Engineer
View Guide
A7
Flow Temperature Sensor Fault
The flow NTC thermistor is giving a reading outside its expected range. Similar to E2, typically…
Medium
Engineer
View Guide
A7 246
Diverter Valve Fault
The diverter valve is not switching correctly between heating and hot water.
Medium
Engineer
View Guide
A8
Return Temperature Sensor Fault
The return NTC thermistor is giving an out-of-range reading.
Medium
Engineer
View Guide
A8 246
DHW Thermistor Fault
The domestic hot water NTC sensor has a fault.
Medium
Engineer
View Guide
B1
PCB Internal Fault
The main Printed Circuit Board has detected an internal error it cannot recover from.
High
Engineer
View Guide
B7
Gas Valve Short Circuit
A short circuit has been detected in the gas valve wiring or the valve itself.
High
Engineer
View Guide
B7 257
Internal Communication Error
There is an internal communication error between boiler components, typically involving the printed circuit board (PCB).
High
Engineer
View Guide
C1
Fan Fault / Air Pressure Switch Fault
The fan is not running at the correct speed or the air pressure switch is not…
High
Engineer
View Guide
C1 221
Flow Sensor Short Circuit
The flow NTC sensor wiring has a short circuit.
Medium
Engineer
View Guide
C1 238
Return Sensor Short Circuit
The return NTC sensor wiring has a short circuit.
Medium
Engineer
View Guide
C4
Flue Temperature Sensor Fault
The flue gas temperature sensor is giving an out-of-range or implausible reading.
Medium
Engineer
View Guide
C4 218
Air Pressure Switch Stuck Closed
The APS is stuck in the closed position.
High
Engineer
View Guide
C6
Fan Speed Error
The boiler fan is not running at the correct speed. This prevents safe ignition as the…
High
Engineer
View Guide
C7
Fan Overspeed Error
The boiler fan is running faster than its rated speed, which can indicate a fault with…
High
Engineer
View Guide
CE 201
Flow Temperature Sensor Fault
The flow temperature sensor (NTC thermistor) has a fault in its wiring or the sensor itself…
Medium
Engineer
View Guide
CE 203
Flow Sensor Fault
The flow temperature sensor is giving an implausible or out-of-range reading.
Medium
Engineer
View Guide
CE 207
Low Water Pressure
The boiler's water pressure has dropped below the safe minimum level. One of the easiest faults…
Low
DIY
View Guide
CE 210
Primary Flow Sensor Fault
The primary flow NTC sensor is giving an out-of-range reading on modern Greenstar models.
Medium
Engineer
View Guide
D1 200
Heating System Circulation Fault
The boiler is detecting poor water circulation in the heating system. The temperature difference between flow…
Medium
Engineer
View Guide
D1 204
Boiler Identification Module Fault
The boiler's identification module (SCB) is not communicating correctly with the main PCB. Usually occurs after…
Medium
Engineer
View Guide
D1 218
Flow/Return Temp Difference Too High
Poor circulation — the temperature gap between flow and return is abnormally large.
Medium
Engineer
View Guide
D3
External Thermostat Short Circuit
The external thermostat or room controller wiring has a short circuit. The boiler cannot receive a…
Medium
Engineer
View Guide
D3 218
External Thermostat Circuit Fault
The wiring from the room thermostat has a fault.
Medium
Engineer
View Guide
D4
System Purge Required / Air in System
Air has been detected in the primary circuit after a period of non-use or maintenance work.…
Low
DIY
View Guide
D5
Primary Flow Thermistor Fault
The main flow temperature sensor is giving an out-of-range reading, preventing the boiler from monitoring water…
Medium
Engineer
View Guide
E2
Flow NTC Sensor Fault
The flow temperature sensor (NTC thermistor) is giving an incorrect reading — either out of range…
Medium
Engineer
View Guide
E2 218
Flow Temperature Sensor Fault
The flow temperature NTC sensor has developed a fault. It may be reading incorrectly or have…
Medium
Engineer
View Guide
E5
Flow Temperature Too High
The boiler flow temperature has exceeded 105°C — the maximum safe limit. A serious overheat condition.
High
Engineer
View Guide
E9
Overheat Fault
The boiler's safety thermostat has detected dangerously high temperatures and triggered a lockout. Usually caused by…
High
Engineer
View Guide
E9 219
Safety Sensor Fault — Temperature Exceeded
The safety temperature sensor has detected a temperature in excess of 105°C, or the sensor contacts…
High
Engineer
View Guide
E9 224
Overheat — Safety Limiter Tripped (Code 224)
The safety temperature limiter has tripped due to overheating. Sub-code 224 typically indicates this occurred during…
High
Engineer
View Guide
E9 277
Safety Sensor High Temperature (GB162)
On Worcester GB162 commercial boilers, code E9 277 means the safety temperature sensor has measured a…
High
Engineer
View Guide
EA 227
Ignition Failure / No Flame Detected
The boiler has failed to detect a flame after four ignition attempts, triggering a safety lockout.…
Medium
DIY
View Guide
EA 229
Flame Loss During Operation
The boiler ignited successfully but then lost the flame during operation. Very common in winter due…
Medium
DIY
View Guide
EA 234
Flame Not Detected After Start
The boiler attempted to start but could not detect a flame. Similar to EA 227, this…
Medium
DIY
View Guide
EA 261
Heat Control Module (HCM) Potentially Defective
On Greenstar i boilers, EA 261 indicates the Heat Control Module (HCM) may be defective. The…
Medium
DIY
View Guide
EA 306
Flame Lost After 10 Seconds
Flame established but lost within 10 seconds.
High
Engineer
View Guide
EA 338
Flame Detected When Not Expected
The boiler has detected a flame signal when the gas valve should be closed. This is…
High
Engineer
View Guide
EF
Maximum Reset Count Exceeded
The boiler has been reset too many times without the underlying fault being resolved, and has…
High
Engineer
View Guide
EF 349
Central Heating Boil Detected
The boiler is operating at minimum burner load but the temperature difference between flow and return…
High
Engineer
View Guide
F0
Internal Component Fault
A general internal fault code indicating a component has failed. The specific sub-code (e.g. F0 238)…
High
Engineer
View Guide
F7
Flame Detected After Shutdown (Unsafe)
The boiler's ionisation circuit is detecting a flame signal when the gas valve should be closed.…
High
Engineer
View Guide
FA
Flue Condensate Blocked / Siphon Full
The condensate siphon inside the boiler is full or blocked, preventing the boiler from starting. Common…
Medium
DIY
View Guide
FA 306
False Flame — Ionisation After Burner Stop
The boiler has detected ionisation current (flame signal) after the burner has been commanded to stop.…
High
Engineer
View Guide
FD
Temperature/Pressure Sensor Combination Fault
Multiple sensor faults have been detected simultaneously, or the temperature/pressure combination is outside safe operating parameters.
High
Engineer
View Guide
FD 231
Mains Power Interrupted During Lockout
The mains power supply was interrupted while the boiler was in a lockout state. This code…
Low
DIY
View Guide
H02
Central Heating Sensor Fault
The central heating temperature sensor is giving an incorrect reading.
Medium
Engineer
View Guide
H02 218
Status: Heating Demand
The boiler is running to satisfy a central heating demand. Normal operation.
Medium
DIY
View Guide
H06
Gas Valve Fault
The gas valve is not operating correctly according to the boiler control system.
High
Engineer
View Guide
H06 218
Status: DHW Demand
The boiler is running to provide hot water. Normal operation.
Medium
DIY
View Guide
H07
Low Water Pressure Warning
A low pressure warning code displayed on some Worcester Greenstar models. The boiler may continue to…
Low
DIY
View Guide
HRE
Boiler Resetting Frequently
The boiler has been resetting itself repeatedly. This indicates a recurring fault that the boiler is…
Medium
Engineer
View Guide