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2967

The temperature difference between supply temperature sensor and temperature sensor at heat exchanger is too large

Worcester Bosch Greenstar 4000 (before May 2021)

Category
B
Remedy
▶ Check the flow through the appliance and that the system is filled.
▶ Check for air locks in the system and purge if required.
▶ Check the isolation valves, ensure they are open.
▶ Check the pump is operating freely and check the voltage to the pump.
▶ Check the heat exchanger sensor and the flow sensor are making correct contact with the heat exchanger assembly/pipework.
▶ Check the heat exchanger sensor for break or short circuit, replace if required.
▶ Check the resistance of the supply sensor for break or short circuit, replace if required.
▶ Check the continuity of harness, replace if required.
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