BoilerFaultCodesYour boiler is struggling to manage the temperature of its internal hot water store, meaning you likely have no hot water available.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: If flashing this indicates either a store thermistor or PCB fault
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with the sensor that monitors the temperature of your stored hot water. The most common reason is that the sensor has developed an electrical fault or the wiring has vibrated loose, preventing the boiler from knowing when to safely heat the water. In rarer cases, the main control board itself may be failing to process the signals it receives.
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 DHW pump — 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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