Red LED illuminated High

Halstead Red LED illuminated Fault Code

Also written as REDLEDILLUMINATED — same fault.

The Halstead Red LED illuminated fault code means: your boiler has detected a safety fault and has locked itself to prevent operation, meaning you currently have no heating or hot water.. It appears on 1 Halstead model in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Safety Lockout. There is a fault condition preventing operation of the appliance (e.g., air pressure switch, water flow switch, or overheat thermostat fault during power up).
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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Halstead models that show the Red LED illuminated fault code

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

Source

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

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