BoilerFaultCodesTechnical description
Boiler type (resistor) malfunction
What causes this fault?
This fault occurs when the boiler's main control board loses communication with the coding resistor, a small component that tells the computer which model it is installed in. The most common reason is a physical failure of the resistor itself or a fault within the main circuit board's memory, which causes the system to shut down because it no longer knows its own safety parameters.
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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