Ariston ecoGENUS 24 MFFI Servicing Instructions page 23

D C
ISPLAY AUSE
A01
Too many attempts to ignite on starting up
A02 After three attempts at ignition, no increase in T was detected
A03 The heating flow temperature exceeds 100°C during operation
A07
Too many failures to flame in one period during operation
A19
The flame was detected after the gas valve had closed
A20
The flame was detected before the gas valve opened
A21
The flow switch does not close
A22
The flow switch does not open
A33 Problem with the fan
A99 Problem with the electronic monitoring
D C
ISPLAY AUSE
E03
Flow temperature over 100°C while boiler is not in operation
(stand-by)
E56
Heating flow temperature probe in open circuit
E66
Heating flow temperature probe
E04 Domestic hot water temperature probe in open circuit
E05 Domestic hot water temperature probe in short circuit
E08 Under floor heating temperature probe in open circuit
E20 Flame detected with gas valve closed
E21
Error in the electrical connection (live and neutral crossed)
E22
Problem with the 50Hz power supply
E23
Flame detection electrode short-circuited
E64
Heating return temperature probe in open circuit
E74 Heating return temperature probe in short circuit
E99 Problem within the electronic system
F
AULTS
1. Drawing D.H.W:
Radiators heat up in summer
mode
2. Drawing D.H.W:
Insufficient hot water temperature
3. Drawing D.H.W:
Noisy operation
4. Decrease/increase heating circuit
pressure
5. When cold water tap turned off, the
boiler ignites
6. Insufficient radiator temperature
T I
ABLE
T II
ABLE
T III
ABLE
P
OSSIBLE
- faulty 3-way valve
- check C.H./D.H.W. temperature probes
- check gas pressures
- check water flow rate
- check secondary heat exchanger
- primary heat exchanger faulty or lime-scale deposits
- low heating system water pressure
- check gas pressures
- check C.H./D.H.W. temperature probes
- check for leaks on the heating circuit
- faulty filling-loop
- faulty secondary heat exchanger
- expansion vessel faulty
- drop in pressure in the water mains, with
consequent water hammer
- check C.H. temperature probe
- check by-pass
- check gas pressures
C
AUSES
23