Vaillant ecoTEC plus 612, Instructions For Use Manual

12

Instructions for use ecoTEC

The boiler will now operate automatically to provide cen-
tral heating for the conditions selected on the external 
controls (ecoTEC combination boilers will also provide 
domestic hot water on demand).
After the boiler stops operating the pump will continue 
to operate for a short period to fully disperse the heat 
from the boiler.

 Note

The boiler incorporates an anti-cycling econo-
miser control to prevent energy wasteful ON 
and OFF operation of the boiler for short peri-
ods when in the central heating mode. When 
turning the room thermostat to a higher setting 
there may therefore be a short delay before the 
boiler operates.

4.7 Status 

displays

bar

i

F

P

plus

pro

2

1

Fig. 4.16  Status displays

The status displays provide information on the operating 
status of the appliance.
• Press the “

i

” button (

1

) to activate the status displays.

The display (

2

) then shows the current status code, for 

example “

S. 4

” for burner operation. The table below 

explains the most important status codes.
In switching phases, for example on starting up again 
after the flame was extinguished, the status message 
“

S.

” briefly appears.

• Press the “

i

” button (

1

) again to switch the display 

back to normal mode.

Display

Meaning

Displays during heating operation

S. 0

No heat required

S. 1

Pump running

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.30

Room thermostat 3/4 no heating demand

S.31

Summer mode active

S.34

Frost protection mode

Displays in hot water operation (ecoTEC combinati-
on 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 (selection, a complete set of status 

codes can be found in the installation and servicing 

manual)

4.8 Troubleshooting

In the unlikely event that a problem occurs with the ope-
ration of the ecoTEC boiler, the following points should 
be checked:

Boiler fails to operate:

–  Is the gas supply turned on (see 4.3.1)?
–  Is the water supply turned on (ecoTEC combination 

boilers only, see 4.3.1)?

–  Is there enough water in the heating system (see 

4.3.2)?

–  Is the electrical supply switched ON?
–  Is the main ON/OFF control in the “ON” position 

(switch position “I”, see 4.4)?

–  Is there an ignition problem (see 4.8.2)?

Hot water operates but no central heating (ecoTEC 
combination boilers only)

-  Is the heating turned ON (see 4.6.1)?
-  Are all external heating controls ON (see 4.6.3)?

 Caution

Inappropriate modifications can cause damage.
If your boiler still does not operate then please 
consult your installer or Vaillant Service 
Solutions (0870 6060 777).

4 Operation