Buderus Logamax plus GB142-24 Servicing Instructions page 54

7 Diagnosis
Blocking boiler-fault code 3A
The air fan has failed during the operating
3 A 2 6 4
phase.
Check that both the plug-and-socket
connections of the blower are correctly fitted.
See page 88, fig 12.
Are the plug-and-socket
connections fitted correctly?
Check blower – activation 120V AC
See page 86.
Is the activation okay?
Check the tacho wire of the blower.
See page 88.
Tacho wire okay?
Check whether you can remedy the fault by
temporarily fitting a new blower.
See page 88, paragraph 8.1.6.
Has the malfunction been repaired?
Check that the mains voltage is
120V AC.
Sufficient mains voltage?
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54 Logamax plus GB142-24/30/45/60 - We reserve the right to make any changes due to technical modifications!
No
Yes
No
Yes
No
Yes
Yes
No
No
Yes
Locking boiler-fault code.
Reconnect the plug-and-socket connection of
the blower. See page 88, fig 12.
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Replace the tacho wire (page 88).
Have the electrical system tested.
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