Appendix
0020181589_04 auroCOMPACT Installation and maintenance instructions
53
Code
Meaning
Cause
F.27
Safety switch-off: Flame simulation
Moisture on the electronics, electronics (flame monitor) defective, gas
solenoid valve leaking
F.28
Failure during start-up: Ignition unsuccessful
Gas meter defective or gas pressure monitor has triggered, air in gas,
gas flow pressure too low, thermal isolator device (TAE) has triggered,
condensate duct blocked, incorrect gas restrictor, incorrect spare part
gas valve, fault on the gas valve, multiple plug on PCB incorrectly
plugged in, break in cable harness, ignition system (ignition transformer,
ignition cable, ignition plug, ignition electrode) defective, ionisation
current interrupted (cable, electrode), incorrect earthing of product,
electronics defective
F.29
Failure during operation: Re-ignition unsuccess-
ful
Gas supply temporarily stopped, flue gas recirculation, condensate duct
blocked, defective earthing of product, ignition transformer has spark
failure
F.32
Fan fault
Plug on fan not correctly plugged in, multiple plug on PCB not correctly
plugged in, break in cable harness, fan blocked, Hall sensor defective,
electronics defective
F.35
Lack of air in combustion unit
Fan speed not correct, air supply or smoke outlet blocked, plug not
correctly connected to fan, multiple plug on PCB not correctly connected,
break in cable harness, fan blocked, Hall sensor defective, electronics
defective
F.42
Coding resistance fault (possible in combination
with F.70)
Short circuit/interruption in output range coding resistance (in cable
harness at heat exchanger) or gas group resistor (on PCB)
F.47
Detachment of hot water sensor in cylinder outlet
(flow rate detection)
NTC defective, NTC cable defective, defective plug connection on NTC
F.48
Hot water sensor short circuit at cylinder outlet
(flow rate detection)
NTC defective, short circuit in cable harness, cable/casing
F.49
Fault: eBUS
Short circuit on eBUS, eBUS overload or two power supplies with differ-
ent polarities on the eBUS
F.52
Mass flow sensor connection fault
Mass flow sensor not connected/disconnected, plug not connected or
incorrectly connected
F.53
Mass flow sensor fault
Gas flow pressure too low, filter under Venturi filter cap wet or blocked,
mass flow sensor defective, internal pressure measuring point in Venturi
blocked (do not use lubricant on Venturi O-ring.)
F.54
Gas pressure fault (in combination with
F.28/F.29)
No or insufficient gas inlet pressure, gas isolator cock closed
F.56
Fault: Mass flow sensor regulation
Gas valve defective, cable harness to gas valve defective
F.57
Fault during comfort safety mode
Ignition electrode highly corroded
F.61
Gas valve control system fault
–
Short circuit/short to earth in cable harness for the gas valve
–
Gas valve defective (coils shorted to earth)
–
Electronics defective
F.62
Gas valve fault, switch-off delay
–
Delayed shutdown of gas valve
–
Delayed extinguishing of flame signal
–
Gas valve leaking
–
Electronics defective
F.63
Fault: EEPROM
Electronics defective
F.64
Fault: Electronics/NTC
Flow or return NTC short circuited, electronics defective
F.65
Fault: Electronics temp.
Electronics overheating due to external influences, electronics defective
F.67
Fault: Electronics/flame
Implausible flame signal, electronics defective
F.68
Fault: Unstable flame signal
Air in gas, gas flow pressure too low, incorrect air ratio, condensate
duct blocked, incorrect gas restrictor, ionisation flow interruption (cable,
electrode), flue gas recirculation, condensate duct
F.70
Invalid device specific number (DSN)
If spare parts fitted: Display and PCB replaced at same time and DSN
not reset, incorrect or missing output range coding resistance
F.71
Flow NTC fault
Flow temperature sensor signalling constant value:
–
Flow temperature sensor incorrectly positioned at supply pipe
–
Flow temperature sensor defective
F.72
Flow/return NTC fault
Flow/return NTC temperature difference too great
→
flow and/or return
temperature sensor defective
F.73
Water pressure sensor signal in the wrong range
(too low)
Interruption/short circuit of water pressure sensor, interruption/short
circuit to GND in supply line to water pressure sensor or water pressure
sensor defective
