BoilerFaultCodes 09
PCB connections / Fault
Baxi Assure 12 System Fault codes & diagnostics
16 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
System Natural Gas 2020-present
GC Number 41-470-85
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Severity at a glance
Each cell = one fault code. Hover to identify. 16 Unrated
Fault codes
All 16 documented codes
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15
PCB connections / Fault
20
Fault flashing
28
Fault flashing
40
Fault flashing
109
Flashing
110
PCB connections / Fault
118
Flashing
125
Circulation fault, primary / Primary water temperature has not changed by 1° C / Flashes after 1 min
128
Burner goes out after 5 seconds
133
Flame failure / Interruption of gas supply
134
Interruption of gas supply, internal error
135
Flow / return sensor temperature test
160
Fan flashing
321
Fault flashing
384
Flame failure / Flashes or re-occurs regularly
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