BoilerFaultCodesYour boiler's internal computer has lost communication with its connected hot water or smart control components due to a settings mismatch.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: System configuration: incompatible BUS device. IPM for cylinder must be set to identification 3 or higher.
What causes this fault?
This fault occurs when the boiler's main control board cannot understand the signals coming from the cylinder or the smart heating controls because they are not properly synced. It is effectively a communication breakdown caused by a settings mismatch or a failure in the electronic module that manages the domestic hot water system.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like Fault 14 / 118 — no call-out fees, no surprises.
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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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