BoilerFaultCodesYour boiler has detected an issue with the sensor that monitors water movement, preventing the system from heating up properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow sensor damaged
What causes this fault?
This fault occurs when the boiler's control board loses communication with the sensor that tracks water moving through the system. The most common reason is that the internal components of the sensor have worn out or developed a spiritual fault, meaning the boiler cannot confirm it is safe to fire up without risking overheating.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E03 — no call-out fees, no surprises.
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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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