Useful Information - Ariston NUOS Serie Manual De Instrucciones

Heat pump water heater
b) Anode (N, Fig. 19):
the heating element anode must be replaced every two years. To replace it, remove the heating element assembly
and unscrew the anode from the support bracket.
c) Evaporator:
verify that the evaporator is not clogged with dust or other particles. To access the evaporator, it is necessary to
remove four fixing screws of the front casing (Fig. 20).
d) Pipe fittings and air ducts:
verify that the external terminal of the air exhaust duct, and the duct, are not obstructed or have not deteriorated.
Carry out the same check for the aspiration duct, if present.
e) Condensate drainage:
check that the condensate outlet is not obstructed and is free of limescale deposits.

8.4 Useful information

If the water comes out cold, check the following:
- whether the terminal board is powered.
- the PCB
- the heating elements
Water comes out boiling hot (steam in the taps)
Disconnect the appliance from the electricity supply and check the following:
- the PCB
- the level of limescale build-up in the tank and on the components
If there is insufficient hot water supply, verify the following:
- water network mains pressure
- the condition of the deflector (jet breaker) on the cold water inlet tube
- the condition of the hot water inlet pipe
- the electrical components
Water dripping from the pressure safety device
During the heating phase, some water may trickle from the tap. This is normal and is not a cause for concern. To
prevent the water trickling, a suitable expansion vessel must be installed on the flow system. If the dripping continues
even after the heating phase, verify the following:
- the calibration of the device
- the water mains pressure
Warning: do not obstruct the device discharge hole!
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