BoilerFaultCodesYour boiler is not receiving enough gas to function properly, which means it cannot fire up safely or consistently.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Gas inlet-pressure too low; check the inlet-pressure during operation at maximum load. Inlet-pressure should amount to at least 20 mbar (25 mbar -17%).
What causes this fault?
This fault occurs when the boiler detects that the gas supply reaching the burner is too weak to maintain a safe flame. The most common reasons are a blockage in the gas pipework, a faulty internal gas valve, or a problem with your external gas meter regulator not providing enough pressure.
This issue often surfaces during the first cold snap of winter, as increased demand for gas across the neighborhood or from other appliances in your home can cause a marginal pressure drop.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 33 — no call-out fees, no surprises.
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