Vaillant ecoTEC plus Operating Instructions Manual page 20

Appendix
Fault
Product does not The heating flow temperature is set
start up: too low or to the Heating off position,
and/or the domestic hot water temperat-
– No domestic
ure is set too low.
hot water
– Heating does
not heat up
The system pressure is insufficient.
Water deficiency in the heating installa-
tion (fault message: F.22).
There is air in the heating installation.
After five unsuccessful ignition attempts,
the product switches to fault mode (fault
message: F.28).
The hydraulic circuit is closed
Domestic hot wa- The external control is not set correctly.
ter generation
functioning cor-
rectly; heating
does not start up.
20
Cause
Operating instructions ecoTEC plus 0020261390_01
Measure
Set the heating flow temperature
and domestic hot water temper-
ature (→ "Setting the heating flow
temperature" section/→ "Setting
the domestic hot water temperat-
ure" section).
Fill the heating installation (→
"Filling the heating installation"
section).
Have your competent person
purge the heating installation.
Press the reset button for one
second. The product carries out
a new ignition attempt.
If the ignition problem is not elim-
inated after three reset attempts,
contact a competent person.
Ensure that the stopcocks for the
hydraulic circuit(s) are open
Set the external control correctly
(→ Control operating instructions).