Buderus Logamax plus Service Manual page 21

6C
is flashing.
After switching off gas flame detected (even the safety valves are closed (leakege))
Control Step
1. Gas valve is defect.
2. Electronic card is defect.
GB012 - 25K
Action
B Switch off the appliance.
B Change the gas valve.
B Switch on the appliance.
B Check the leakage.
B Press RESET button and restart again.
6C failure still exist? -->2.
B Switch off the appliance.
B Cut mains supply.
B Change the electronic card.
B Connect to main supply.
B Switch on the appliance.
Failures / Errors 3
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