Main Heating · Eco Compact Combi 25–30
125 boiler fault code
Main Eco Compact Combi models 25–30
Get a Gas Safe engineer
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Renting? Report it to your landlord or housing provider first. They are responsible for gas safety and boiler repairs, and the repair should not cost you.
What 125 means
Primary circulation fault.
Safe check
Read and note code 125 or E125 and any visible pressure reading. Do not vent, dismantle or try to free internal parts.
When to contact an engineer
Arrange a Gas Safe registered engineer to diagnose the primary circulation and internal pump or electrical components.
Safety notice
A boiler fault code alone is not a gas or carbon-monoxide emergency. If you smell gas, a CO alarm sounds, anyone feels unwell, or there is an unsafe flame, leave and call 0800 111 999 from outside.
Source and provenance
- Main Eco Compact Combi User Guide · models 25–30 · pressure instructions p. 14; §7.1, printed p. 21
user guide
Model 25–30; document copy publishes no revision
- Baxi Professional error-code table · legacy Baxi 600 Combi & System group
professional error-code table
Checked 29/09/2026; the online table publishes no revision