Installation
51
Burner connection, Burner control wiring (VD2/VD2A/CT3 only)
For burners with plug-in connection
The burner cables are included in the
standard delivery of the Vitotronic.
Connect the burner in accordance with
applicable codes.
A
To boiler control unit
B
To burner
Terminal codes
L1
Phase via fixed high limit to the
burner
?
Ground connection
N
Neutral connection to the burner
T1,T2 Control circuit
S3
Connection for burner fault
indicator
B4
Connection for burner hours
counter
A
To plug-in connection in connection
enclosure
B
To burner
1.
Disconnect power to burner and
boiler control.
2.
Connect plugs
fA
and plug
lÖ
to
respective counter plugs in boiler
control unit.
3.
Connect the 7-pole plug
fA
and
the 3-pole plug
lÖ
to the burner.
Terminal codes
1,2,3 Control circuit ”2nd stage
burner or modulation controller”
(via two-point controller with
2-stage operation; via three-
point controller with modulating
operation)
1
From burner
2
Modulating down
3
Modulating up/2nd stage ON
Colour codes as applicable
BK
Black
BN
Brown
BU
Blue
5285
941
-
0
1
A
B
41
120 VAC
