BoilerFaultCodesYour boiler's internal computer has lost its connection with the main control panel, meaning the system can't send or receive the signals needed to heat your home.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Communication error with control unit
What causes this fault?
This fault occurs when the boiler's internal electronic brain loses its ability to talk to the control panel or the main sensors. It is usually caused by a loose connection in the internal wiring or a critical component failure on the main circuit board. Over time, heat and vibration inside the unit can dry out solder joints or cause plugs to become slightly unseated, breaking the communication loop.
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 E37 — no call-out fees, no surprises.
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