BoilerFaultCodesYour boiler's computer brains are not talking to each other correctly because a security code needs to be re-entered after a repair.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: After replacing both components, after being turned on, the appliance goes to fault and displays the error message “F70”.
What causes this fault?
This fault occurs when the boiler's main control board and the display screen are not compatible or have not been properly introduced to each other. It usually happens after a repair where one of these parts was replaced but the unique software code for your specific boiler model wasn't entered. Without this identity code, the two components cannot communicate and the boiler will not fire up for safety reasons.
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 F70 — 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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