BoilerFaultCodesTechnical description
Temporary fault code (Refer to section 7.10)
What causes this fault?
This fault occurs when the boiler's main control board loses reliable communication with its internal sensors or fails to read the temperature data correctly. The most common reason is an electronic glitch or a failing main circuit board that can no longer process signals from the thermistors. In some cases, it can also be triggered by a faulty sensor sending an unstable voltage back to the control centre.
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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