Viessmann VITODENS 200-W Service Instructions Manual page 42

Codes
Code 2
(cont.)
Value Internal cir-
address culation
34: ... pump
4 Control
funct.
5 Control
funct.
6 Control
funct.
7 Control
funct.
8 OFF
9 OFF
10 OFF
11 OFF
12 OFF
13 OFF
14 OFF
15 OFF
16 ON
17 ON
18 ON
19 ON
20 ON
21 ON
22 ON
23 ON
Coding in the delivered condition
Boiler/burner
38:0 Status burner control unit:
Operational (no fault)
51:0 Internal circulation pump
is always started when
there is a heat demand
42
Heating cir- Heating cir-
cuit pump cuit pump
Heating cir- Heating cir-
cuit without cuit with
mixer mixer
OFF Control funct.
OFF Control funct.
OFF OFF
OFF OFF
Control funct. Control funct.
Control funct. Control funct.
Control funct. OFF
Control funct. OFF
OFF Control funct.
OFF Control funct.
OFF OFF
OFF OFF
Control funct. Control funct.
Control funct. Control funct.
Control funct. OFF
Control funct. OFF
OFF Control funct.
OFF Control funct.
OFF OFF
OFF OFF
Possible change
38:≠0
51:1
Circulation pump for
cylinder heating
Control funct.
OFF
Control funct.
OFF
Control funct.
OFF
Control funct.
OFF
Control funct.
OFF
Control funct.
OFF
Control funct.
OFF
Control funct.
OFF
Control funct.
OFF
Control funct.
OFF
Fault burner control unit
When there is a heat
demand, the internal circu-
lation pump will only be
started when the burner is
operational. System with
heating water buffer cylin-
der.