BoilerFaultCodesIdeal AIR FLOW FAULT Fault Code
Also written as AIRFLOWFAULT — same fault.
The Ideal AIR FLOW FAULT fault code means: your boiler has stopped working because it cannot safely exhaust fumes or confirm that the internal fan is moving air correctly.. It appears on 1 Ideal model in our database.
Technical description: Check fan rotates. Replace if necessary. Check pressure switch. Replace if necessary. Replace detection probe.
What causes the Ideal AIR FLOW FAULT fault?
This fault occurs when the boiler's safety system cannot confirm that the fan is successfully clearing combustion gases from the unit. The most common reasons include a mechanical failure of the fan motor, a blockage in the flue pipe, or a faulty sensor that is incorrectly reporting a lack of airflow. Without this constant flow of fresh air, the boiler shuts down to prevent dangerous fumes from building up.
This issue can occur more frequently during periods of high winds, which can create back-pressure in the flue and interfere with the air pressure switch readings.
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 AIR FLOW FAULT fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ideal AIR FLOW FAULT 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