BoilerFaultCodesYour boiler is having trouble communicating with the temperature thermostat built into its control panel, which means it doesn't know how warm your home is.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Room temp sensor faulty: There is a circuit break on the room temperature sensor built into the FW 100.
What causes this fault?
This fault occurs when the electrical connection between the boiler's main control board and its built-in digital thermostat is interrupted. The most common reason is a physical breakage in the internal wiring or a component failure within the controller itself, which prevents the boiler from receiving the temperature data it needs to operate.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like Fault 03 / 20 — no call-out fees, no surprises.
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