5 / Y High

Ideal 5 / Y Fault Code

Also written as 5Y — same fault.

The Ideal 5 / Y fault code means: your boiler's electronic control system has frozen or locked up, preventing it from functioning correctly.. It appears on 1 Ideal 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: Control panel locked.
Typical repair cost £150-350 (including labour)

Engineer required

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

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Ideal models that show the 5 / Y fault code

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

Source

Ideal 5 / Y fault code information on this page is sourced and cross-checked against the official Ideal service / installation manuals for each affected model.

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