BoilerFaultCodesIdeal 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 4 Ideal models in our database.
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.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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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.
- Ideal Classic SE15P FF manual (PDF)
- Ideal Logic Max Heat 2 manual (PDF)
- Ideal Maximiser SE manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026