BoilerFaultCodesYour boiler's computer brain has become confused and is no longer recognising its own internal components.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal fault: Incorrect module type detected.
What causes this fault?
This fault occurs when the boiler's main control board loses communication with the unique memory chip that contains the unit's specific settings. It is usually caused by a physical hardware failure within the electronics or a loose connection on the circuit board itself, preventing the boiler from knowing which model it is supposed to be. In some cases, a significant electrical surge can also corrupt this internal data, causing the system to shut down for safety.
This fault is often seen after heavy summer thunderstorms, as power surges from lightning strikes can damage the sensitive electronic components on the main circuit board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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