BoilerFaultCodesYour boiler is not receiving enough gas to stay lit safely, which is preventing it from heating your home or water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Minimum gas pressure
What causes this fault?
This fault occurs when the boiler detects that the incoming gas supply is too weak to maintain a stable flame. The most common reason is a blockage or mechanical failure in the gas valve, but it can also be caused by an external issue with your gas meter or its regulator. When the pressure drops below a safe threshold, the boiler shuts down as a safety precaution to prevent unstable combustion.
This fault is more common during extreme cold spells, as high demand on the gas grid or freezing of external gas regulators can cause supply pressures to drop.
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 426 — no call-out fees, no surprises.
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