Ariston Nuos Split Flex 200L, Manual

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Heat pump water heater – OPERATING AND MAINTENANCE INSTRUCTIONS
53
To be able to operate also on appliances with a two-tier rate system, the control logic calculates the number of average
hours a day during which the power supply is available in the economy mode (HC).
A self-learning function ensures that the appliance reaches the pre-set temperature in the time range during which the
economy rate applies; the maximum limit of hours is determined by the P9 TIME_W parameter; after the initial start-up
(or after switching off the hardware), the default setting is 8 hours. In order to optimize the self-learning function it is
advisable to set AUTO mode.
7.12 Anti-frost function
In any event, if the temperature of the water in the tank falls below 5 °C while the appliance is powered, the heating
element (1000 W) will be automatically activated to heat the water up to 16 °C.
7.13 Faults
As soon as a fault occurs, the appliance enters into the fault mode while the display emits flashing signals and visualises
the error code. The water heater will continue supplying hot water provided the fault affects only one of two the heating
units, by activating the heat pump or heating element.
If the fault involves the heat pump, the symbol "HP" will flash on the screen, while the heating element symbol will flash
if the fault involves this component. If both components are affected, both symbols will flash.
Error
code
Cause
Heating
element
operation
Heat pump
operation
What to do
E1
Heating occurs without any water in
the water tank
OFF OFF
Turn off the appliance. Verify the causes of the lack of
water (leakage, faulty hydraulic connections, etc.)
E2
Excessive temperature of the water
in the tank
OFF OFF
Turn the appliance off then wait until the water
temperature decreases; if the problem persists, contact
the technical assistance service
E4 Sensor fault – heating element zone OFF OFF
Check or replace the heating element zone sensors, if
necessary
E5
Excessive difference between the
temperatures of the heating
element zone sensors
OFF OFF Check or replace the sensors, if necessary
H2 Circuit in low pressure or fan fault ON OFF
Turn off the appliance. 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 evaporator sensor.
H3 Compressor fault or gas leak ON OFF
Turn off the appliance. Check that the evaporator is not
obstructed. Verify whether the wirings and the compressor
functions properly and/or check for any refrigerant gas
leakages. Check or replace the evaporator sensor.
H4 Evaporator obstructed ON ON
Turn off the appliance. Check that the evaporator and the
external unit casing is not obstructed.
H5 Fan fault ON OFF
Turn off the appliance. Verify that there are no physical
impediments to the movement of fan blades, check the
wiring of connection with circuit boards. Check the
evaporator sensor.
H6 Air sensor fault ON OFF
Check the proper connection of the probe cable between
the two units, Verify whether the sensor is properly
connected and positioned, and replace it if necessary.
H7 Evaporator sensor fault ON OFF
Check the proper connection of the probe cable between
the two units, Verify whether the sensor is properly
connected and positioned, and replace it if necessary.
H8 Hot water sensor fault ON OFF
Verify whether the sensor is properly connected and
positioned, and replace it if necessary
H9 Active defrost fault ON
OFF
(if air
temperature il
below 5°C)
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 that the
external unit casing is not obstructed.
F1 PCB fault OFF OFF
Try turning the appliance off then on again and verify the
operation of the control boards, if necessary replace it.
F2
Excessive number of ON/OFF
(RELEASE)
OFF OFF
Temporarily disconnect the product mains and the
batteries.
F3
Lack of communication between the
PCB and interface
OFF OFF
Try turning the appliance off then on again and verify the
operation of the control boards or replace them, if
necessary.