BoilerFaultCodesWorcester Bosch FAIL POINT D Fault Code
Also written as FAILPOINTD — same fault.
The Worcester Bosch FAIL POINT D fault code means: your boiler is not receiving a signal from your thermostat or internal timer telling it to turn on.. It appears on 4 Worcester Bosch models in our database.
Technical description: No heat demand. Room thermostat, mains programmer (or link), or electronic programmer at ST5 failure. Red diode may be damaged.
What causes the Worcester Bosch FAIL POINT D fault?
This fault occurs when there is a break in the communication link between your controls and the boiler's main computer. It typically happens because the mechanical timer has worn out or the batteries in your wall thermostat have died, meaning the boiler never receives the 'on' command. In some cases, the internal electronic board that processes these signals has developed a fault and can no longer recognize when heat is being requested.
This issue is frequently seen during the first cold snap of autumn when homeowners try to turn their heating back on after it has been switched off all summer.
DIY fix possible
Check that your room thermostat is turned up higher than the current room temperature.Replace the batteries in your wireless room thermostat if it has them.Ensure your programmer or timer is set to 'ON' or 'AUTO' and that the clock is showing the correct time.
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Gas Safe Register →Worcester Bosch models that show the FAIL POINT D fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Worcester Bosch FAIL POINT D fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026