29 High

Ideal 29 Fault Code

The Ideal 29 fault code means: your boiler has failed to detect a flame, which means it cannot stay on safely and has stopped working for your protection.. It appears on 2 Ideal models 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: Check the connection of the ionisation pin, use the pin to measure the ionisation current in series (this current should amount to at least 2 µAC).

What causes the Ideal 29 fault?

This fault occurs when the boiler's control system cannot confirm that a flame has successfully lit, causing it to shut down for safety. The most common reasons are a worn-out sensor that can no longer 'see' the flame, a build-up of carbon on the probe, or a faulty internal component failing to send the ignition spark.

Typical repair cost £120-280 (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 29 fault code

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

Source

Ideal 29 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