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811

Hot water heating: thermal disinfection failed

Worcester Bosch Greenstar 4000 System

Category
A
Remedy
▶ If water is being drawn constantly, take action to stop this.
▶ Position the DHW temperature sensor correctly.
▶ Check that there is contact between the DHW cylinder temperature sensor and the cylinder.
▶ Vent the cylinder circuit.
▶ Set DHW heating to "priority".
▶ Check plate heat exchanger for calcification.
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