Vaillant 0010002778, Installation Instructions Manual

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Installation instructions geoTHERM VWS/VWW 0020057444_01
74
Fault code Error text/description
Emergency
mode
Possible cause Remedy
91 Brine pressure too low
Pressure < 0.2 bar
Heat pump shuts down and
goes into operation automat-
ically when the pressure
rises above 0.4 bar
possible Pressure drop in the heat source
system as a result of leakage or air
lock. Check heat source system for leaks, top
up brine, bleed.
Brine pressure sensor defective. Check the plug contact on the PCB and
the cable harness, check pressure sensor
for correct functioning, replace pressure
sensor.
L1 and N connections on the PCB in-
terchanged. Check L1 and N connections on the PCB
and connect correctly if necessary.
94 Phase loss Check circuit
breaker
One or more phases dropped
out.
possible Loss of a phase or a circuit breaker
has tripped. Check circuit breakers and cable connec-
tions (power supply to the compressor).
Badly tightened electrical connec-
tions. Check electrical connections.
Mains voltage too low. Measure voltage at heat pump terminal
box.
Power company block on incorrectly
set E-plan (e.g. E–plan 1). Check E-plan setting.
Start-up current limiter defective or
incorrectly connected. Check start-up current limiter.
95 Wrong direction of rotation.
Change comp. phases
Phase sequence not correct
possible Phases switched over. Change the phase sequence by switching
over 2 phases at a time on the mains
feed.
Start-up current limiter defective or
incorrectly connected. Check start-up current limiter.
96 Error - sensor fault
Short circuit in pressure sen-
sor
possible A pressure sensor in the cooling cir-
cuit is defective or not properly
plugged in. Check the plug contact on the PCB and
the cable harness, check pressure sensor
for correct functioning, replace pressure
sensor.
Table 10.4 Fault-induced shutdown (cont.)
10.6 Other errors/malfunctions
Fault indication Possible cause Remedy
The auxiliary heating does not function,
even though it has been enabled by the con-
troller (e.g. when the supply has been
blocked by the power supply company
(Power company blockage)); the heating or
the domestic hot water cylinder do not
reach the desired temperature. The auxiliary heating is tied to a low-rate
tariff which has been blocked by the power
company. Check whether the auxiliary heating is on a
low-rate tariff and a power company block-
age is in effect.
The safety thermostat (STB) on the auxiliary
heating has tripped. Release the STB by pushing the button.
Possible causes if the thermostat trips again:
Air in the heating system. Blocked dirt filters
in the heating system return line. Bleed the heating circuit. Clean the blocked
dirt filters.
The heating circulation pump has stopped or
is running too slowly. check the heating circulation pump and re-
place if necessary.
Noises in the heating circuit. Air in the heating circuit. Bleed the heating circuit.
Dirt in the heating circuit. Flush the heating circuit.
"Out T. aux htr on" incorrectly set. Change "Out T. aux htr on" (Menu A3).
Pump defective. Check functioning of the pump; replace if
necessary.
Traces of water beneath or next to the ap-
pliance. The condensate drain is blocked. Condensate in the interior of the unit is col-
lected in the condensate pan and, if neces-
sary, fed away under the unit (not a fault).
Check the insulation on the pipes in the inte-
rior of the unit and re-insulate, if necessary,
to reduce the accumulation of condensate.
Leaks from the heating circuit. Check the heating circuit components
(pump, auxiliary heating, pipes) for leaks.
If necessary, retighten the screw couplings
and replace the seals.
Outside temperature indicates - 60 ºC. Outside temperature sensor defective. Check outside temperature sensor.
Temperatures in the heating circuit too cold
or too warm. Room target temp. not optimally set
Change room target temp. (Menu 1).
Set-back temp. not optimally set
Change set-back temp. (Menu 1).
Heating curve not optimally set. Change heating curve (Menu C2).
Table 10.5 Other errors/malfunctions
10 Troubleshooting and diagnostics