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Greenstar 27-30 i System
Worcester Bosch Greenstar 27-30 i System
9A
HCM (Heat Control Module) fitted incorrectly
9U
HCM (Heat Control Module) error
b7
Internal error
C6
Fan problem
C7
Fan problem / no airflow
D1
Return sensor error / temperature too high
E2
Flow sensor error
E5
Flow temperature too high
E9
Safety sensor temperature too high / thermostat activated
EA
Flame / ignition error
F0
Internal error
F7
Flame error
FA
False flame error / gas valve leak
FD
Mains power error
Fb
Gas valve EV1 leak test failed
A1
Pump stuck or running in air
C1
Airflow stopped during operation
C4
Airflow present during last 24 hours
D4
Temperature difference between flow and safety sensors exceeds limit
EF
Central heating boil detect - large delta T despite minimum burner
No code
Temperature or sensor issues
Source:
Manufacturer manual (PDF)
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