BoilerFaultCodesTechnical description
Additional relay control ecoTec
What causes this fault?
This fault occurs when the boiler's main control centre loses its connection to an extra electrical component, such as an external pump or specialized heating control. The most common reason is a loose connection in the internal wiring or a component failure within the electronic control board. Because the boiler can no longer coordinate with these essential external parts, it shuts down to prevent any mechanical damage.
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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