Firebird 16 Fault Code
The Firebird 16 fault code means: your boiler has lost the connection to the temperature sensor responsible for your hot water, meaning it cannot accurately heat your taps.. It appears on 1 Firebird model in our database.
Technical description: Water DHW thermistor anomaly (THMdhwt) - Loose, disconnected, broken or short-circuited connector
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Firebird models that show the 16 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Firebird 16 fault code information on this page is sourced and cross-checked against the official Firebird service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026