Benchmark ZWB 7-29 CC1 Installation And Servicing page 89

Fd
and
Button pressed without necessity
Check
1.
Button is flashing.
2. The PCB control board is damaged.
7 181 465 346 GB (03.02)
flashing.
Failure identification procedure
Action
B Press
, restart the appliance.
Fd? ↓2.
B Make a note of the altered service settings (see
table 1, "First Service Level; Values that can be
modified" at page 8 and table 5, "Secondary
Service Level; Values that can be modified" at
page 11).
B Power OFF the appliance.
B Disconnect the boiler electrical connection.
B Change PCB control board.
B Reconnect the boiler electrical connection.
B Turn ON the appliance.
B Restore service settings previously noted down.
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