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D1

Return sensor error / temperature too high

Worcester Bosch Greenstar CDi Compact Combi

Cause 240 (Locking)
Return sensor error. Sensor wet or damaged (the boiler will block for 300 secs before this condition).
Action
Reset button
Cause 241 (Locking)
Return sensor error. Sensor disconnected or damaged (the boiler will block for 300 secs before this condition).
Action
Reset button
Cause 286 (Locking)
Return temperature too high. Boiler overheat
Action
Reset button
Cause 240 (Blocking)
Return sensor short circuit. Wet sensor. Blocking for 300 secs before going to Locking error.
Cause 241 (Blocking)
Return sensor disconnected. Blocking for 300 secs before going to Locking error.
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