BoilerFaultCodesTechnical description
Safety relay open when should be closed
What causes this fault?
This fault occurs when the boiler's internal computer detects that a critical safety switch on the circuit board has failed to move into the correct position. The system shuts down immediately because it can no longer verify that the gas and ignition components are being controlled safely. The most common reason is that the electrical contacts on the main control board have worn out or become stuck over time.
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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