Operating instructions

ManualsBrandsViessmann ManualsDomestic AppliancesVitodens 222-F

106

Dis-

played

fault

code

Const. Weath.-

comp.

System char-

acteristics

Cause Measures

A9 X The burner

operates at its

lower output if a

heating circuit

with mixer is

connected.

The burner is

blocked if only

one heating cir-

cuit without

mixer is con-

nected.

Internal circu-

lation pump

blocked

Check the circula-

tion pump

b0 X X Burner blocked Short circuit,

flue gas tem-

perature sen-

sor

Check the flue gas

temperature sen-

sor

b1 X X Control mode

as per deliv-

ered condition

Communica-

tion error,

programming

unit

Check connections

and replace the

programming unit if

required

b5 X X Control mode

as per deliv-

ered condition

Internal fault Replace the control

unit

b7 X X Burner blocked Boiler coding

card faulty

Plug in boiler cod-

ing card or replace,

if faulty

b8 X X Burner blocked Lead break,

flue gas tem-

perature sen-

sor

Check the flue gas

temperature sen-

sor

bA X Mixer regulates

to a flow tem-

perature

of 20 °C

Communica-

tion error,

extension kit

for heating

circuit 2 (with

mixer)

Check extension

kit connections and

code

Troubleshooting

Fault codes

(cont.)

5457 552 GB