BoilerFaultCodesTechnical description
Burner & Fault Indicator Neon
What causes this fault?
This fault occurs when the internal water temperature exceeds a safe limit, causing the overheat thermostat to shut the system down to prevent damage. The most common reasons are a pump failure that stops water from moving or a blockage within the main heat exchanger that restricts flow. It can also be triggered by trapped air in the pipework or a faulty sensor providing an incorrect temperature reading.
This fault is more common in autumn when heating systems are first turned on after being idle all summer, as stagnant water can cause the pump to seize or stick.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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