BoilerFaultCodesYour boiler is having trouble controlling the flow of water through the system, which is likely affecting your hot water or heating performance.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow regulation valve
What causes this fault?
This fault occurs when the internal motor fails to accurately control the water flow through the heat exchanger, preventing the boiler from managing temperatures correctly. The most common reason is that the mechanical valve has become stiff or seized due to a buildup of debris, or the electronic motor that turns it has failed.
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 C0 — no call-out fees, no surprises.
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Worcester Bosch WR325 RSF 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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