Ariston NUOS 200 EXT Instructions D'utilisation page 68

Heat pump water heater – OPERATING AND MAINTENANCE INSTRUCTIONS FOR THE USER
Error
Cause
code
Heating occurs without any
E1
water in the water tank
Excessive temperature of the
E2
water in the tank
Fault during heating with the
E3
heating element
Sensor fault – heating element
E4
zone
Excessive difference between
E5 the temperatures of the heating
element zone sensors
Excessive pressure in the
H1 refrigeration circuit, or faulty
reading on the pressure switch
H2 Fan fault
H3 Compressor fault
H4 Evaporator obstructed
H6 Air sensor fault
H7 Evaporator sensor fault
H8 Hot water pipe sensor fault
H9 Active defrost fault
F1 PCB fault
Excessive number of ON/OFF
F2
(RESET)
Lack of communication
F3
between the PCB and interface
Empty tank (EMPTY),
F4 impressed current anode circuit
open
Short-circuit on the impressed
F5
current anode circuit
Heating
Heat pump
element
operation
operation
OFF OFF
OFF ON
OFF ON
OFF ON
OFF ON
ON OFF
ON OFF
ON OFF
ON OFF
ON OFF
ON OFF
ON OFF
ON OFF
OFF OFF
ON ON
ON ON
ON ON
ON ON
68
What to do
Verify the causes of the lack of water (leakage, faulty
hydraulic connections, etc.)
Turn the appliance off then on again; if the problem
persists, contact the technical assistance service
Verify that the heating element functions properly
Check or replace the heating element zone sensors, if
necessary
Check or replace the sensors, if necessary
Try restarting the machine; if the error persists, contact
the technical assistance service
Check that the fan is not broken and that the evaporator
is not obstructed. Check whether the hot gas valve
functions properly and replace it if necessary. Check the
perfect cleaning of grids and ducts
Verify whether the compressor functions properly and/or
check for any refrigerant gas leakages
Check the perfect cleaning of grids and ducts
Verify whether the sensor is properly connected and
positioned, and replace it if necessary
Verify whether the sensor is properly connected and
positioned, and replace it if necessary
Verify whether the sensor is properly connected and
positioned, and replace it if necessary
Check that the fan is not broken and that the evaporator
is not obstructed. Check whether the hot gas valve
functions properly and replace it if necessary. Check the
perfect cleaning of grids and ducts
Try turning the appliance off then on again and verify
the operation of the control boards, if necessary
Temporarily disconnect the product and the batteries
Try turning the appliance off then on again and verify
the operation of the control boards or replace them, if
necessary
Verify whether there is any water in the tank, check or
replace the impressed current anode, if necessary
Check or replace the impressed current anode if
necessary