E Overview Of Fault Codes - Vaillant ecoTEC exclusive 627 Installation And Maintenance Instructions Manual

E 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.
Code Parameter
F.00 Interruption: Flow sensor
F.01 Interruption: Return sensor
F.02 Interruption: DHW outlet sensor
F.03 Interruption: Cylinder sensor
F.10 Short circuit: Flow sensor
F.11 Short circuit: Return sensor
F.12 Short circuit: DHW outlet sensor
F.13 Short circuit: Cylinder sensor
F.20 Safety switch-off: Temperature limiter
F.22 Safety switch-off: Low water pressure
F.23 Safety switch-off: Temp.spread too large
F.24 Safety switch-off: Temp. incr. too fast
F.25 Safety switch-off: Flue temp. too high
F.26 Fault: Fuel valve not working
F.27 Safety switch-off: Flame simulation
F.28 Start-up failure: Ignit. unsuccessful
F.29 Operating failure: Ignit. unsuccessful
F.32 Fault: Fan
F.33 Pressure switch
52
Possible causes
NTC plug not plugged in or has come loose, multiple plug on the PCB
not plugged in correctly, interruption in cable harness, NTC defective
NTC plug not plugged in or has come loose, multiple plug on the PCB
not plugged in correctly, interruption in cable harness, NTC defective
Only in conjunction with F.91
NTC defective, NTC cable defective, defective plug connection on NTC,
defective plug connection on the actoSTOR electronics
Only in conjunction with F.91
NTC defective, NTC cable defective, defective plug connection on NTC,
defective plug connection on the actoSTOR electronics
NTC defective, short circuit in cable harness, cable/housing
NTC defective, short circuit in cable harness, cable/housing
Only in conjunction with F.91
NTC defective, short circuit in cable harness, cable/housing
Combination product: Warm start sensor/cylinder sensor short circuit
Combination product with actoSTOR: Short circuit cylinder sensor (NTC)
only in combination with F.91
NTC defective, short circuit in cable harness, cable/housing
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
Only in liquefied petroleum gas operation or in cascade mode: The
differential pressure sensor was not replaced with a bypass valve; the
bypass valve is not functional
No or insufficient water in the product, water pressure sensor defective,
cable to pump or water pressure sensor loose/not connected/defective
Pump blocked, insufficient pump output, air in product, flow and return
NTC connected the wrong way round
Pump blocked, insufficient pump output, air in product, system pressure
too low, non-return valve blocked/incorrectly installed
Break in plug connection for optional flue gas safety cut-out (SCO),
break in cable harness
Gas valve assembly stepper motor not connected, multiple plug on the
PCB not plugged in correctly, interruption in cable harness, gas valve
assembly stepper motor defective, electronics defective
Moisture on the electronics, electronics (flame monitor) defective, gas
solenoid valve leaking
Gas meter defective or gas flow monitor has triggered, air in gas, gas
flow pressure too low, thermal cut-out has triggered, condensate route
blocked, incorrect gas injector, incorrect spare part gas valve assembly,
value in D.052 does not correspond to the printed value on the current
gas valve assembly, fault on the gas valve assembly, multiple plug on
PCB incorrectly plugged in, break in cable harness, ignition system
(ignition transformer, ignition cable, ignition plug, ignition electrode)
defective, ionisation flow interrupted (cable, electrode), incorrect earthing
of product, electronics defective
Gas supply temporarily stopped, flue gas recirculation, condensate route
blocked, defective earthing of product, ignition transformer has spark
failure
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
Check: Cable harness, vacuum hose (blockage), supply air/flue gas
route (blockage), panel (correct type), flue pipe (length), air pressure
sensor, settings (if necessary, switch D.132 to multiple-flue configura-
tion), pressure switch, fan.
Installation and maintenance instructions ecoTEC exclusive 0020193966_04