13
Operating instructions ecoTEC plus 937
Display
Meaning
Displays during heating operation
S. 0
No heat required
S. 1
Pump running
S. 2
Heating pump supply
S. 3
Ignition sequence (heating operation)
S. 4
Burner ignited
S. 6
Fan and pump overrun
S. 7
Pump overrun
S. 8
Anti cycling mode (after heating operation)
S.31
Summer mode active
S.34
Frost protection mode
Displays in hot water operation (ecoTEC
combination boilers only)
S.10
Hot water demand
S.14
Burner ignited
Displays for hot holding operation (ecoTEC
combination boilers only)
S.20
Hot holding request
S.24
Hot burner holding operation on
Displays in cylinder charging mode (ecoTEC system
boilers only)
S.20
Cylinder charging request
S.24
Cylinder charging burner on
Table 4.1 Status codes and what they mean (selection)
4.7
Troubleshooting
In the unlikely event that a problem should arise during
operation of the ecoTEC, you should first check the
following yourself:
Boiler fails to operate:
– Is the gas supply OK (see Section 4.2.1)?
– Is the water supply OK (see Section 4.2.1)?
– Is there sufficient water in the heating system (see
Section 4.2.2)?
– Is the electrical supply switched on?
– Is the main switch in position "ON" (switch position "l“,
see Section 4.3)?
– Is there an ignition problem (see Section 4.7.2)?
Hot water operates but no central heating
(ecoTEC plus 800 & 937 only):
– Is the heating switched on (see Section 4.3)?
– All the external controller set to the "
ON
“ position
(see Section 4.5.3)?
a
Caution!
Inappropriate alterations can cause damage!
If your boiler still does not operate properly
after checking the above points, please contact
your expert technician or Vaillant Service
Solutions (0870 6060 777).
4.7.1
Faults caused by water pressure too low
The device switches to "
Fault
" if the filling pressure in
the heating system is too low. This malfunction is
indicated by the fault code "
F.22
"
(dry fire) or "
F.23
"
or
"
F.24
"
(lack of water).
You can only start up the appliance again when the
heating system is sufficiently filled with water.
4.7.2 Faults
in
ignition
bar
i
F
P
1
2
Fig. 4.15 Troubleshooting
If the burner fails to ignite after five attempts, the
device does not start up and switches to "
Fault"
. This is
indicated by the fault code "
F.28
or "
F.29
in the display.
In addition, the display shows a flame symbol with a
cross through it (
1
).
Automatic ignition can only take place after you
manually
reset the fault
.
• To reset the fault, press the reset button (
2
) and hold
it down for one second.
a
Caution!
If the boiler still fails to start up after three
attempts please contact an expert technician
or Vaillant Service Solutions.
4.7.3
Faults in the air/flue gas routing
The appliances are fitted with a fan. If the fan does not
work properly, the appliance will switch itself off.
The display shows the symbols
and
and the error
message "
F.32
”
h
Note
Please have the fault code to hand when you
contact Vaillant Service Solutions since this
will help in troubleshooting.
Operation 4