Code
Display text
Description
Solution
E.01.12
Return Higher Flow
Return tempearture has a higher
temperature value than the flow tem
perature
Flow and return reversed:
Bad connection: check the wiring and connec
tors
Water circulation in wrong direction: check the
circulation (direction, pump, valves)
Incorrectly fitted sensor: check that the sensor
has been correctly fitted
Malfunctioning sensor: check the Ohmic value
of the sensor
Faulty sensor: replace the sensor
E.02.04
Parameter Error
Parameter Error
Configuration error:
Reset CN1 and CN2
See
The data plate for the CN1 and CN2
values.
E.02.13
Blocking Input
Blocking Input of the Control Unit
from device external environment
Blocking input is active:
External cause: remove external cause
Wrong parameter set: check the parameters
E.02.15
Ext CSU Timeout
External CSU Timeout
CSU time out:
Bad connection: check the wiring and connec
tors
Faulty CSU: Replace CSU
E.02.17
GVC CommTimeout
Gas Valve Control unit communica
tion has exceeded feedback time
Communication error with the security kernel:
Restart the boiler
Replace the CU-GH
E.02.35
Safety device lost
Safety critical device has been dis
connected
Communication fault
Carry out an auto-detect
E.02.47
Failed Conn Funct Gr
Failed Connecting Function Groups Function group not found:
Carry out an auto-detect
Restart the boiler
Replace the CU-GH
E.02.48
Funct Gr Conf Fault
Function Group Configuration Fault
-
E.02.52
Gvc Burner Prof Err
Gvc Burner Profile Error
-
E.02.70
HRU test error
External heat recovery unit test
failed
-
E.04.00
Parameter error
Safety parameters Level 5 are not
correct or missing
Replace the CU-GH.
E.04.01
TFlow Closed
Flow temperature sensor is either
shorted or measuring a temperature
above range
Flow temperature sensor short circuited:
Bad connection: check the wiring and connec
tors
Incorrectly fitted sensor: check that the sensor
has been correctly fitted
Faulty sensor: replace the sensor
E.04.02
TFlow Open
Flow temperature sensor is either
removed or measuring a tempera
ture below range
Flow temperature sensor open:
Bad connection: check the wiring and connec
tors
Faulty sensor: replace the sensor
E.04.03
Max Flow temp
Measured flow temperature above
savety limit
No flow or insufficient flow:
Check the circulation (direction, pump, valves)
Check the water pressure
Check the cleanliness of the heat exchanger
12 Troubleshooting
172
C 340 / C 640
7762666 - v.02 - 29092020
