BoilerFaultCodesYour boiler has detected that a temperature sensor is sending an unusual reading, suggesting it may have been knocked out of place or is reporting a sudden, impossible heat spike.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Temperature sensor fitted in wrong location.
What causes this fault?
This fault occurs when the boiler detects a sudden, rapid temperature rise that seems physically impossible under normal operation. It usually happens because the temperature sensor has become loose, has been clipped into the wrong position, or is failing and sending incorrect electrical signals to the internal computer.
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 Fault 53 128 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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