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Installation and servicing instructions for wall-mounted condensing gas boiler Buderus 600 - 11R/19R/24R • 02/2006
Buderus • http://www.buderus-domestic.co.uk
Subject to modifications resulting from technical improvements!
Servicing
5
Code
Meaning
7A
Voltage in burner-control unit too low (lower than 187 V~) or too high (higher than 246 V~)
Possible
cause
Action
1
Regulating device may have to cope with interference
– Check if for example induction fields interfere with the
regulating device
– Check if the are any peaks in the electrical network
Code
Meaning
7C
Mains supply interrupted
Possible
cause
Action
1
A problem with the mains supply
Check the mains supply during operation (230V~)
2
Reset button pressed too briefly
Press the Reset button until "r" appears in the display
Code
Meaning
7F
F3 fuse defect, or burner control unit error
Possible
cause
Action
1
Short circuit in the 24V circuit (three-way-valve or
connector)
Check for a short circuit and replace the F3 fuse
2
Regulating device may have to cope with interference
– Check if for example induction fields interfere with the
regulating device
– Check if the are any peaks in the electrical network
Code
Meaning
7H
Voltage peaks in the UBA
Possible
cause
Action
1
Regulating device may have to cope with interference
– Check if for example induction fields interfere with the
regulating device
– Check if the are any peaks in the electrical network
Code
Meaning
7L
Internal UBA error
Possible
cause
Action
1
Regulating device may have to cope with interference
– Check if for example induction fields interfere with the
regulating device
– Check if the are any peaks in the electrical network
