BoilerFaultCodesWhat the manual says
Manufacturer manualHigh temperature protection: Over-temperature thermostat on heat exchanger activated; No water flow through heat exchanger; Over-temperature thermostat fault or bad connection; PCB over-temperature condition; Flue fault resulting in recirculation or activation of air pressure switch
From this model's manual
Verified against the Baxi/Baxi 600 Heat installation & service manual.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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All 18 fault codes on the 600 Heat
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