0020230531_06 ecoFIT pure Installation and maintenance instructions
45
Status code
Meaning
S.98
Automatic test programme: Return temperature sensor, heating demands blocked.
S.99
Internal automatic test programmes
S.108
Purging the combustion chamber, fan in operation
S.109
Product's standby mode activated
D
Overview of fault codes
Note
Since the code table is used for various products, some codes may not be visible for the product in question.
Fault code
Meaning
Possible cause
F.00
Fault: Flow temperature sensor
NTC plug not plugged in or has come loose, multiple plug on the PCB not
plugged in correctly, interruption in cable harness, NTC sensor defective
F.01
Fault: Return temperature sensor
NTC plug not plugged in or has come loose, multiple plug on the PCB not
plugged in correctly, interruption in cable harness, NTC sensor defective
F.10
Short circuit: Flow temperature sensor
NTC sensor defective, short circuit in the cable harness, cable/housing
F.11
Short circuit: Return temperature sensor
NTC sensor defective, short circuit in the cable harness, cable/housing
F.12
and
F.91
Short circuit: Cylinder temperature
sensor
NTC sensor defective, short circuit in the cable harness, cable/housing
F.13
Short circuit: Domestic hot water cylinder
temperature sensor
NTC sensor defective, short circuit in the cable harness, cable/housing
F.20
Safety shutdown: Overheating temperat-
ure reached
Incorrect earth connection between cable harness and product, flow or return
NTC defective (loose connection), stray spark via ignition cable, ignition plug
or ignition electrode
F.22
Safety shutdown: Water deficiency in the
boiler
No or insufficient water in the product, water pressure sensor de-
fective, cable to the pump or to the water pressure sensor loose/not
connected/defective
F.23
Safety shutdown: Temperature spread
too great (NTC1/NTC2)
Pump blocked, insufficient pump output, air in product, flow and return NTC
sensors connected the wrong way round
F.24
Safety shutdown: Temperature rise too
fast
Pump blocked, insufficient pump output, air in product, system pressure too
low, non-return valve blocked/incorrectly installed
F.25
Safety shutdown: Flue gas temperature
too high
Break in plug connection for optional flue gas safety cut-out (SCO), break in
cable harness
F.27
Safety shutdown: Fault in flame detec-
tion
Moisture on the electronics, electronics (flame monitor) defective, gas solen-
oid valve leaking
F.28
Fault: Ignition unsuccessful when starting
up
Gas meter defective or gas pressure switch has triggered, air in gas, gas
flow pressure too low, thermal cut-out has triggered, incorrect gas injector,
incorrect spare gas valve assembly, fault on the gas valve assembly, mul-
tiple plug on PCB incorrectly plugged in, break in cable harness, ignition sys-
tem (ignition transformer, ignition cable, ignition plug, ignition electrode) de-
fective, ionisation flow interrupted (cable, electrode), incorrect earthing of
product, electronics defective
Condensate siphon blocked
F.29
Fault: Flame loss
Gas supply temporarily stopped, flue gas recirculation, incorrect earthing of
product, ignition transformer has spark failure
Condensate siphon blocked
F.32
Fan frost protection function active: Fan
speed outside the tolerance values
Plug on fan not correctly plugged in, multiple plug on PCB not correctly
plugged in, break in cable harness, fan blocked, Hall sensor defective, elec-
tronics defective
F.49
eBUS fault: Voltage too low
Short circuit on eBUS, eBUS overload or two power supplies with different
polarities on the eBUS
F.61
Fault: Gas valve assembly control
Short circuit/short-to-ground in cable harness to gas valve assembly, gas
valve assembly defective (coils shorted to earth), electronics defective
F.62
Fault: Gas valve switch-off control
Delayed switch-off of gas valve assembly, delayed extinguishing of flame
signal, gas valve assembly leaking, electronics defective
F.63
Fault: EEPROM
Electronics defective
F.64
Fault: Electronics/sensor/analogue-to-
digital converter
Flow or return NTC short circuited, electronics defective
F.65
Fault: Electronics temperature too high
Electronics overheating due to external influences, electronics defective
