BoilerFaultCodesYour boiler has detected an unsafe level of heat or an electrical fault in its safety sensor and has locked down to prevent damage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The contacts for the safety temperature sensor have shorted or the safety temperature sensor has detected a temperature higher than 130°c
What causes this fault?
This fault occurs when the boiler's internal safety components detect that the heat exchanger has reached a dangerously high temperature or there is a failure in the electrical sensor that monitors it. The most common reasons are a lack of water flow caused by a pump failure, a heavy build-up of debris in the system, or a faulty sensor sending an incorrect signal to the control board.
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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