Boilers 6 min read Updated 28 June 2026 Trade verified
Baxi Boiler Fault Codes — Complete UK Reference
Baxi combis show E-prefixed codes on the digital display. Common faults are ignition, overheat and PCB. Here is the trade reference by model.
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Step-by-step method
E133 — Gas supply / ignition failure
Boiler failed to light. Check gas, condensate trap, electrode gap (4mm).
E110 — Overheat lockout
Flow temperature too high. Blocked heat exchanger or pump fault. Requires flush.
E125 — Circulation fault
Pump not moving water. Check pump is not seized and PRV isn't stuck open.
E168 — General fault
PCB communication error. Reset once; if persistent, PCB replacement £260–£380.
Frequently asked questions
Where is the Baxi reset button?+
On the front panel, marked with a flame or 'R'. Hold for 3 seconds.
Is Baxi as good as Worcester Bosch?+
For heat-only and system boilers, yes — the Baxi 800 Heat is class-leading. For combis, Worcester still edges it.