Vaillant flexoTHERM exclusive VWF 57/4 230V, Installation And Maintenance Instructions Manual

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Installation and maintenance instructions 0020213395_04
Code Meaning Cause
Remedy
F.788 Building circuit: Pump fault
–
The electronics system of the high-
efficiency pump has detected a
fault (e.g. dry running, blockage,
overvoltage, undervoltage) and has
switched off and locked the pump.
–
Switch the heat pump off for at least
30 seconds (no current)
–
Check the quality of the plug contact
on the PCB
–
Check that the pump functions cor-
rectly
–
Purging the building circuit
F.792 Sensor fault: VI inlet temp.
–
Sensor not connected or sensor in-
put has short-circuited
–
Check the sensor, and replace if
necessary
–
Replace the cable harness
F.793 Sensor fault: EEV-VI outlet temp.
–
Sensor not connected or sensor in-
put has short-circuited
–
Check the sensor, and replace if
necessary
–
Replace the cable harness
F.797 Sensor fault: Cooling flow temp.
–
Sensor not connected or sensor in-
put has short-circuited
–
Check the sensor, and replace if
necessary
–
Replace the cable harness
F.798 Sensor fault: Well inlet temp.
–
Sensor not connected or sensor in-
put has short-circuited
–
Check the sensor, and replace if
necessary
–
Replace the cable harness
F.799 Sensor fault: Well outlet temp.
–
Sensor not connected or sensor in-
put has short-circuited
–
Check the sensor, and replace if
necessary
–
Replace the cable harness
F.1100 Immersion heater: Safety cut-out
open The safety cut-out on the electric back-
up heater is open due to:
–
Insufficient volume flow or air in the
building circuit
–
The immersion heater is operated
when the building circuit is not filled
–
Immersion heater operation at flow
temperatures above 110 °C trips the
safety fuse of the safety cut-out and
requires that the fuse be replaced
–
Feed-in of external heat into the
building circuit
–
Check the circulation in the building
circuit pump
–
If required, open the stopcocks. The
safety cut-out is automatically reset
as soon as the temperature at the
fuse falls below 55 °C again.
Also press
reset
.
If the safety cut-out is still open at an
electric back-up heater temperature
below 55 °C, temperatures above
110 °C were reached and the safety
fuse tripped.
–
Replace the safety cut-out
–
Reduce or stop the external heat
that is entering
F.1117 Compressor: Phase failure
–
In-rush current limiter defective or
incorrectly connected
–
Defective fuse
–
Poorly tightened electrical connec-
tions
–
Mains voltage too low
–
Compressor/low tariff power supply
not connected
–
Blocked by energy supply company
for over three hours
–
Check the fuse
–
Check the electrical connections
–
Measure voltage at the heat pump
electrical connection
–
Reduce energy supply company
anti-cycling time to under three hours
F.1118 Compressor: Incorrect phase seq.
–
Incorrect order of phase connection
to the grid feed-in
–
In-rush current limiter defective or
incorrectly connected
–
Change the phase order by switch-
ing over two phases at a time to the
grid feed-in
–
Check the in-rush current limiter
F.1119 Compressor: ICL fault
–
In-rush current limiter defective or
incorrectly connected
–
Mains voltage too low
–
Check all plug contacts
–
Checking the ICL compressor con-
nection
–
Check the ICL control PCB connec-
tion
–
Replace the ICL
F.1120 Immersion heater: Phase failure
–
The circuit breaker in the electronics
box has been triggered.
–
Electric back-up heater defective
–
Poorly tightened electrical connec-
tions
–
Mains voltage too low
–
Blocked by energy supply company
for over five hours
–
Check the electric back-up heater
and its power supply, and reset the
circuit breaker
–
Check the electrical connections
–
Measure the voltage at the electrical
connection for the electric back-up
heater