BoilerFaultCodesYour boiler has encountered an internal electronic communication error that is preventing it from monitoring its own performance correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Emissions test mode - Internal fault analog converter
What causes this fault?
This fault occurs when the boiler's internal computer is unable to process the data it receives from its electronic sensors. The most common reason is a component failure on the main circuit board, which prevents the system from accurately measuring how the boiler is burning gas.
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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