80 Installation and maintenance instructions 0020308121_04
Code/meaning Possible cause Measure
F.078
The control centre is not sup-
ported by the unit.
Fault in the electrical connection
for the domestic hot water con-
nection temperature sensor
1. For products without integrated domestic hot water genera-
tion: Check whether the bridge on plug X2 betwen contacts
2 and 5 is plugged in and is without interruption.
2. If the bridge is working correctly, check and, if necessary,
replace the wiring harness between the PCB and sensor.
F.080
The cold water inlet temperat-
ure sensor in the internal cylin-
der is defective.
Inlet temperature sensor defect-
ive or not connected
▶ Check and, if required, replace the NTC sensor, plug, wiring
harness and the PCB.
F.081
Cylinder charging has failed.
Interruption in the wiring har-
ness
▶ Check the wiring harness to the internal cylinder.
Secondary heat exchanger
clogged/blocked
▶ Check the secondary heat exchanger for dirt.
Pump non-return valve blocked ▶ Check that the non-return valve for the pump in the internal
cylinder is working correctly.
Plug on domestic hot water
connection temperature sensor
loose/not plugged in
▶ Check the plug and the plug connection for the domestic hot
water connection temperature sensor.
Domestic hot water connection
temperature sensor installed
incorrectly
▶ Check whether the temperature sensor on the domestic hot
water connection is correctly installed on the pipe.
Pump blocked ▶ Check that the pump in the internal cylinder is working cor-
rectly.
The pump is defective. ▶ Replace the pump in the internal cylinder.
3-port diverter valve defective or
blocked
▶ Check and, if required, replace the 3-port diverter valve.
Impeller sensor in the shift-load
cylinder is defective
▶ Check and, if required, replace the impeller sensor in the shift-
load cylinder.
F.083
When the burner starts, no tem-
perature increase is registered
at the flow or return temperat-
ure sensor or the temperature
increase here is too slow.
System pressure too low ▶ Check the system pressure.
Flow temperature sensor: No
contact
▶ Check whether the flow temperature sensor is lying against the
flow pipe correctly.
Fault in the electrical connection
for the flow temperature sensor
▶ Check and, if required, replace the wiring harness between the
PCB and sensor, including all plug connections.
Return temperature sensor: No
contact
▶ Check whether the return temperature sensor is lying against
the return pipe correctly.
Fault in the electrical connec-
tion for the return temperature
sensor
▶ Check and, if required, replace the wiring harness between the
PCB and sensor, including all plug connections.
Insufficient/no water in the
product.
1. Fill the heating installation.
2. Check the product and the system for leakages.
F.084
The temperature difference
between the flow and return
temperature sensors returns im-
plausible values.
Flow temperature sensor in-
stalled incorrectly
▶ Check whether the flow temperature sensor has been installed
correctly.
Return temperature sensor in-
stalled incorrectly
▶ Check whether the return temperature sensor has been in-
stalled correctly.
Flow and return temperature
sensors inverted
▶ Check whether the flow and return temperature sensor has
been installed correctly.
F.085
The NTC sensors are installed
incorrectly.
Flow/return temperature
sensors have been installed on
the same pipe/wrong pipe
▶ Check that the flow and return temperature sensors have been
installed on the correct pipe.
F.087
The ignition transformer is not
connected to the PCB.
Fault in the electrical connection
for the ignition transformer
▶ Check the wiring harness between the PCB and ignition trans-
former, including all plug connections.
Defective ignition transformer ▶ Check that the ignition transformer is working correctly and, if
required, replace it.
F.088
The electrical connection to the
gas valve has been interrupted.
Gas valve assembly not con-
nected
▶ Check the connection to the gas valve assembly.
Gas valve assembly connected
incorrectly
▶ Check the connection to the gas valve assembly.
Short circuit in the wiring har-
ness
▶ Check the wiring harness and, if required, replace it.
F.089
The installed heating pump
does not match the unit type.
Incorrect pump connected ▶ Check whether the pump that is connected is the one that is
recommended for the product.
To Next Page
Loading...
Need help?
General