DeDietrich AFC 18 User Manual page 36

8 Troubleshooting
Code Faults
D17 DHW 2 S.FAIL
D18 SOL.HW S.FAIL
D19 SOL.COL.S.FAIL
D20 SOL COM.FAIL
D27 PCU COM.FAIL
D37 TA-S SHORT-CIR SCU
D38 TA-S
DISCONNEC
D99 DEF.BAD PCU
36 AFC
Cau Description
se of
the
fault
SCU Sensor fault on tank 2
SCU Solar tank sensor fault
SCU Header sensor fault
SCU
SCU
SCU
SCU
Check/solution
Poor connection
Sensor failure
Contact the professional who handles the mainte­
nance for the appliance
Poor connection
Sensor failure
Contact the professional who handles the mainte­
nance for the appliance
Poor connection
Sensor failure
Contact the professional who handles the mainte­
nance for the appliance
Switch the boiler off and switch it back on.
Contact the professional who handles the mainte­
nance for the appliance
Communication failure between the SCU and PCU
PCBs.
Contact the professional who handles the mainte­
nance for the appliance
The Titan Active System® has short circuited.
Contact the professional who handles the mainte­
nance for the appliance
Remarks: Domestic hot water production has stop­
ped but can nonetheless be restarted using the
key. The tank is no longer protected. - If a tank with­
out Titan Active System® is connected to the boiler,
check that the TAS simulation connector (delivered
with package AD212) is fitted to the sensor PCB.
The Titan Active System® is on an open circuit.
Contact the professional who handles the mainte­
nance for the appliance
Remarks: Domestic hot water production has stop­
ped but can nonetheless be restarted using the
key. The tank is no longer protected. - If a tank with­
out Titan Active System® is connected to the boiler,
check that the TAS simulation connector (delivered
with package AD212) is fitted to the sensor PCB.
The SCU software version does not recognise the
PCU connected
Contact the professional who handles the mainte­
nance for the appliance
300026440 - v06 - 07082018