How much does it cost to fix Baxi error code L5?

Typical repair cost for the Baxi L5 fault is £180-350 including labour.

L5 High

Baxi L5 Fault Code

Q: What does the Baxi L5 fault code mean?

Your boiler is struggling to switch between heating your radiators and providing hot water, which means you will likely have no hot water or central heating until it is fixed.

The Baxi L5 fault code means: your boiler is struggling to switch between heating your radiators and providing hot water, which means you will likely have no hot water or central heating until it is fixed.. It appears on 1 Baxi model in our database.

Technical description: Diverter Valve Fault

Typical repair cost £180-350 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Baxi models that show the L5 fault code

Click a model for the full fault code list and model-specific repair notes.

130 HE (range) Repair: £180-350

Source

Baxi L5 fault code information on this page is sourced and cross-checked against the official Baxi service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026