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3.3.Repairs
The following operations must be performed solely by the competent personnel, such as
the local distributor or the service provider.
Electric heating unit seasonal checks
The following checks to the electric heating unit are recommended at least once a year:
The control system and the protection system (three phase fuse, electric connections
tightening, temperature sensors and safety elements etc.) should work properly.
Check and clean the heating elements of any limestone deposits.
When cold, the pressure inside the installation should be 1 bar. Otherwise, adjust the
reference value.
Check and restore the expansion vessel's air cushion, if needed; the pressure should be 0.9-1 bar.
Check the proper operation of the circulating pump.
3.4.Faults remedy
Diagnosis
The electric heating unit is fitted with an advanced self-diagnosis system which displays the faults
codes in case of breakdown on the LCD screen.
Certain faults (code “A”) may lead to the unit's shutdown. To resume operation, press the reset key
for a second.
In case of shutdown due to other faults (code “F”), the electric heating unit can automatically resume
its operation when the parameters which caused the fault returned to normal.
The table below shows some fault causes, as well as certain solutions for the users.
In the case of a repeating fault which you cannot remedy, please contact the Ferroli service
personnel.
Check the wiring's and connection strip's integrity; they should not have damages due to heating.
Symptoms Code Possible causes Solutions
No heating A01
Electric leakages (deficiencies in the power
supply)
Check if the unit is connected to the power
supply system and if the three phase fuse is
coupled. Ask the authorized personnel to
perform this check.
Heating temperature limiter faulted.
Check if the heating temperature limiter is
correctly mounted and actuated.
There is no circulation in the system.
Check the circulating pump to see if there is
circulation in the heating system.
There is air in the system.
The water in the heating system is not
recirculated.
There is air in the heating system.
Disconnected temperature sensor A08
The heating temperature sensor is not fixed or
is faulty (normally, subsequently to a 10-minute
heating, the temperature increases on the
temperature sensor and on the domestic hot
water sensor do not exceed 3°C. Temperatures
above 40°C are not detected).
Check if the heating temperature sensor is
properly connected to the pipe.
Faulty heating temperature sensor F10
Faulty heating temperature sensor, such as
open circuit, short-circuit, or unfixed or
interrupted cables.
Check the cables or replace the temperature
sensor.
Faulty return pipe temperature sensor F11
Faulty NTC return pipe sensor, for reasons
such as open circuit, short-circuit, or improperly
fixed or interrupted cables.
Check the cables or replace the temperature
sensor.
Faulty doemstic hot water (DHW) tank
temperature sensor
F14
Faulty NTC DHW sensor, for reasons such as
open circuit, short-circuit, or improperly fixed or
interrupted cables.
Check the cables or replace the temperature
sensor.
Fill the system with water.
Check the water pressure switch and, if
needed, replace it.
Check the open position of the valves.
Check the Y filter.
Check the circulating pump.
Lack of circulation in the system F41
Clogged heating circuit.Faulty operation of the
circulating pump.
Check the recirculating pump to see if there is
circulation in the heating system.
Faulty water pressure switch F37
Not enough water pressure in the installation.
The water pressure switch has open or faulty
contacts.
Temperature limiter either faulty or operated A03
Temperature in the unit is above 90°C A06
EN