BoilerFaultCodesYour boiler is staying at a fixed temperature rather than adjusting its flame to meet your heating needs efficiently.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Go to section 'G'
What causes this fault?
This fault occurs when the boiler cannot adjust the size of its flame to match the temperature you have set, causing it to run at a single, inefficient heat level. The most common reason is a failure in the communication between the control board and the gas valve, often due to a faulty electrical coil or a sticking internal component. Without this ability to 'modulate', the boiler loses its efficiency and may struggle to maintain a consistent temperature in your home.
This fault is often more noticeable during the first cold spell of autumn, when the system is required to work harder and more dynamically after being idle over the summer.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like Burner output does not modulate — no call-out fees, no surprises.
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Potterton Performa 30 HE is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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