Strebel S-CB Px 120, Installation Operating & Maintenance Manual

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S-CB Px 120 Manual 94
Cause:
Bad flue gas and/or air supply system.
Corrective action:
Check if the design of the flue gas and air supply system complies with the max. com-
bined resistance as specified.
Check if the flue gas and air supply system is installed according a good installation prac-
tice by a skilled installer.
Check all seals in the flue gas and air supply system.
Cause:
External factors.
Corrective action:
Check if there were extreme weather/wind conditions when the fault occurred.
Check if the boiler room pressure is equal to the pressure at the position of the flue gas
outlet. (When combustion air is drawn from the boiler room).
Display message
F10
F a l s e f l a m e s i g n a l
p u m p o n 9 9 9 , 5 h r s
Reason Flame signal detected, while boiler should not fire for operation.
Cause:
The flame detection circuit detects a flame which is not supposed to be present.
Corrective action:
Check the ignition/ionisation electrode and make sure it is clean (or replace it).
Check the power supply voltage for a correct polarity.
Check the power supply for bad frequency or voltage peaks.
Check external wiring for voltage feedback.
Check the internal wiring for bad connections.
Check if the gas valve is closing correctly.
Replace the burner control.
Display message
F11
F a n s p e e d i n c o r r e c t
p u m p o n
9 9 9 , 5 h r s
Reason Actual fan speed differs from the unit rpm set point.
Cause:
An incorrect fan speed is detected.
Corrective action:
Check the 4 wired wiring and connections at the fan and at the main control board.
Check the 3 wired power supply wiring and connections at both ends.
Replace the fan.
Replace the main control board.
Display message
F12
p r o g r a m m i n g e n d
p u m p o n 9 9 9 , 5 h r s
Reason Programming of the parameters completed successfully.
Cause:
Programming of the parameters completed successfully.
Corrective action:
This message occurs to confirm the end of programming. Pressing RESET will return the
unit in normal operating status.