BoilerFaultCodesTechnical description
Boiler operates with continuous relay test
What causes this fault?
This fault occurs when the boiler's internal electronic controller gets trapped in a perpetual diagnostic loop during its start-up sequence. It is typically caused by a hardware failure on the main circuit board where the internal switches fail to release or communicate correctly, preventing the system from ever reaching the ignition stage.
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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