40
Displayed
fault code
System characteris-
tics
Cause Measures
b0 Burner blocked Short circuit, flue
gas monitoring
sensor
Check sensor (see
page 43).
b8 Burner blocked Lead break, flue
gas monitoring
sensor
Check sensor (see
page 43).
Repairs
Checking and cleaning the plate heat exchanger
Shut off and drain the boiler on the heat-
ing water and DHW sides.
Note
Residual water may drain from the plate
heat exchanger during removal.
Troubleshooting
Fault indicators on the display
(cont.)
5848 649 GB