Baxi · 600 Combi
E118 boiler fault code
Baxi 600 Combi legacy generation
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What E118 means
Primary heating-system water pressure is low; the Baxi table defines this as below 0.5 bar.
Safe check
Read and note E118 and the visible pressure reading without opening the boiler. Stop if the gauge or display is unclear.
When to contact an engineer
Arrange a Gas Safe registered engineer if pressure remains low or falls again; do not attempt an internal repair.
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
- 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