PILOT WILL NOT STAY ALIGHT Emergency

Chaffoteaux PILOT WILL NOT STAY ALIGHT Fault Code

Also written as PILOTWILLNOTSTAYALIGHT — same fault.

The Chaffoteaux PILOT WILL NOT STAY ALIGHT fault code means: your boiler's small starter flame keeps blowing out or failing to stay lit, which prevents the main boiler from igniting and providing heating or hot water.. It appears on 5 Chaffoteaux models in our database.

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description: I) Thermocouple not working; II) Thermo-electric valve faulty; III) Gas pressure low/variable; IV) Terminal wrongly positioned; V) Badly assembled flue; VI) Gas pressure too hight
Typical repair cost £120-250 (including labour)

Engineer required

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

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Chaffoteaux models that show the PILOT WILL NOT STAY ALIGHT fault code

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

Source

Chaffoteaux PILOT WILL NOT STAY ALIGHT fault code information on this page is sourced and cross-checked against the official Chaffoteaux service / installation manuals for each affected model.

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