BoilerFaultCodesYour boiler has lost its connection to the temperature sensor that monitors the main heat exchanger, causing the system to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler temperature sensor lead break
What causes this fault?
This fault occurs when the electrical connection between the boiler's main control board and its primary temperature sensor is severed. The most common reason is a physical break in the wiring, a loose plug, or the internal failure of the sensor's delicate electrical components due to age and heat stress.
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 38 — no call-out fees, no surprises.
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