Fault Codes; Fault Memory - Vaillant ecoTEC plus Instructions For Installation And Servicing

10 Troubleshooting
Display Meaning
d.78 Storage charging temperature limit (target flow
temperature in storage mode, system boilers only)
d.80 Heating operating hours
d.81 Water heating operating hours (when accessories
are fitted)
d.82 Cycles in heating mode
d.83 Cycles in hot water operation
d.84 Maintenance indicator: Number of hours until the
next maintenance
d.93 DSN appliance variant setting
d.96 Factory setting
1) Five-digit numbers are saved with the diagnostics codes 80 to 83. If d.80, for example, is selected, only the first two digits of the
number are displayed (e. g. 10). The display switches to the last three digits (e. g. 947) by pressing "i". In this example the number
of operating hours of the heating is 10947 h. The display returns to the selected diagnostics item by pressing "i" again.
Table 10.3 Diagnostics codes of the second diagnostic level (continued)
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 alternately for about two seconds each.
Code Meaning
F. 0 Flow–NTC open circuit
F. 1 Return–NTC open circuit
F.10 Flow NTC short circuit
F.11 Return NTC short circuit
F.13 Tank NTC short circuit
F.20 Safety temperature limiter by NTC
activated
F.22 Dry fire
F.23 Water shortage, temperature difference
between flow and return NTC too large
F.24 Water shortage, temperature rise too
quick
Table 10.4 Error codes
42
Display value/adjustable value
Adjustment range in °C 55 to 90 (Factory setting: 80)
1
in h )
1
in h )
Quantity/1001) (3 corresponds 300)
Quantity/1001) (3 corresponds 300)
Adjustment range: 0 to 3000 h and "-" for disabled
Factory setting: "-" (300 corresponds to 3000 h)
Adjustment range: 0 to 99
1 = Resetting adjustable parameters to factory setting
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 display mode, proceed
as follows:
• Press the "i" button below the display or
• Do not touch any key for about four minutes.
The display will now revert back to showing the
current flow temperature.
Cause
NTC broken, NTC cable broken, Defective connection at NTC, Defective
connection at electronics
NTC broken, NTC cable broken, Defective connection at NTC, Defective
connection at electronics
NTC defective, short circuit in cable harness, cable/casing short cut
NTC defective, short circuit in cable harness, cable/casing short cut
NTC defective, short circuit in cable harness, cable/casing short cut
Flow-NTC not correctly thermal-connected or defective; appliance does not
shut down
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
Pump blocked or defective, pump output too low, flow and return NTC
interchanged
Pump blocked, insufficient pump output, air in appliance, water pressure too
low
Installation and Servicing ecoTEC plus