Vaillant ecoTEC plus SERIES Instructions For Installation And Servicing - page 36
Instructions for installation and servicing ecoTEC plus / 0020020828_05
36
10.1.3 Fault
codes
Fault codes take priority over all other display functions
in the event of a system fault occurring.If multiple faults
occur, the corresponding fault codes are displayed alter-
nately for about two seconds each.
10.1.4 Fault
memory
The fault memory stores details of the ten most recent faults.
• Press the ”i” and ”–” buttons simultaneously.
• Use the ”+” button to scroll back through the list of
memorised errors. To cancel fault error memory dis-
play mode, proceed as follows:
• Press the ”i” button below the display or
• Do not touch any key for about four minutes. The dis-
play will now revert back to showing the current flow
temperature.
Code Meaning
Cause
F. 0
Flow–NTC open circuit
NTC broken, NTC cable broken, Defective connection at NTC, Defective connec-
tion at electronics
F. 1
Return–NTC open circuit
NTC broken, NTC cable broken, Defective connection at NTC, Defective connec-
tion at electronics
F.10
Flow NTC short circuit
NTC defective, short circuit in cable harness, cable/casing short cut
F.11
Return NTC short circuit
NTC defective, short circuit in cable harness, cable/casing short cut
F.13
Tank NTC short circuit
NTC defective, short circuit in cable harness, cable/casing short cut
F.20 Safety temperature limiter by NTC activated
Flow-NTC not correctly thermal-connected or defective; appliance does not shut down
F.22
Dry fire
Too little water in the appliance, water pressure sensor defective, cable to pump
or water sensor defective, pump blocked or defective, pump output too low
F.23
Water shortage, temperature difference
between flow and return NTC too large
Pump blocked or defective, pump output too low, flow and return NTC interchan-
ged
F.24 Water shortage, temperature rise too quick
Pump blocked, insufficient pump output, air in appliance, water pressure too low
F.27
Incorrect sensing of flame
Flame detector defective
F.28 Appliance does not start: Attempts to
ignite during start failed
Faults in the gas supply such as:- - Gas meter or gas pressure detector defective -
Air in gas- Gas flow pressure too low - Fire protection tap has disengaged Faults
in the gas valve, wrong gas setting, igniter (ignition transformer, ignition cable,
ignition plug) defective, ionisation current stopped (cable, electrode), faulty
earthing in appliance, electronics defective
F.29 Flame goes off during operation and
subsequent
ignition attempts failed Gas supply temporarily stopped, faulty earthing of appli-
ance
F.32
Fan speed variation
Fan blocked, plug not inserted correctly on fan, hall sensor defective, fault in
cable harness, electronics defective
F.49 eBUS under voltage
Short circuit on eBUS, overload on eBUS or two power sources on eBUS with dif-
ferent polarity
F.61
Gas–valve control defective
Short circuit/earth (ground) leak in cable harness to gas valves, gas valve assembly
defective (earth/ground leak from coils), electronic control system defective
F.62 Gas valve shut off delay
Gas valve leaking, electronics defective
F.63 EEPROM error
Electronics defective
F.64 Electronics/NTC fault
Short-circuit in flow or return NTC or electronics defective
F.65 Electronics temperature too high
Electronics too hot due to external effect, electronics defective
F.67 Flame detector input signal is outside the
limits (0 or 5 V)
Electronics defective
F.70 No valid DSN in display and/or main board
Spare part failure display and main board interchanged at same time and device
specific number not adjusted
F.71
Flow NTC reports constant value (stuck at)
Flow NTC is defective
F.72
Flow and/or return NTC fault
Flow and/or return NTC is defective (tolerances too big)
F.73
Water pressure sensor signal out of range
(too low)
Spare part failure display and main board interchanged at same time and device
specific number not adjusted
F.75
No pressure rise was detected on turning
on the pump
Water pressure sensor or/and pump defective Air in the heating system, quick
bleeder defective Too little water in appliance; check adjustable by-pass; connect
external expansion vessel to return
F.76 Overheating protection on primary heat
exchanger triggered
Cable or cable connection of fuse in the primary heat exchanger defective, or pri-
mary heat exchanger defective
F.77
Condensate pump or feedback of
accessories blocks heating
Condensate pump defective or flume flap feedback triggered
F.78 Wrong configuration with accessory
link box VR65 connected to combination boiler
con
No communication to main board
Connection error display main board
Table 10.4 Error codes
10 Troubleshooting