BoilerFaultCodesIdeal HA Fault Code
The Ideal HA fault code means: your boiler has developed a communication or hardware circuit error that has caused it to stop providing both heating and hot water.. It appears on 3 Ideal models in our database.
Technical description: Boiler is not working for central heating or hot water and the display shows ‘HHHHH:::::AAAAA ’ (flashing).
What causes the Ideal HA fault?
This fault occurs when the boiler's internal communication system suffers a total breakdown, essentially meaning the different electronic parts can no longer 'talk' to each other. The most common reason is a physical failure within the main circuit board or a malfunction in the control knobs that prevents the boiler from receiving instructions. Because the brain of the boiler cannot verify the system is safe or functional, it shuts down entirely as a precaution.
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 HA fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ideal HA 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