Viessmann Vitodens 200, Service Instructions Manual

Page: 31 / 116

31
Troubleshooting
Cause Check
Break in the BUS connection to
the variable speed heating circuit
pump or
faulty pump
Check the cable connection to the heating
circuit pump
or
check the heating circuit pump
Short circuit/break in the BUS
connection to the extension kit
for the heating circuit with mixer
Check cable connection to the extension
kit (plugĂ"X
Ă
5").
Check coding acc. to the heating system
design.
Check correct connection via "Brief scan"
ć Control unit with standard
programming unit see pageĂ76.
ć Control unit with Comfortrol
programming unit see pageĂ94.
Break in the BUS connection to
the Comfortrol programming unit
Check the cable connections to the
programming unit
Sensor inputs are not properly
read
Check the correct sensor connections on
plugsĂ"X
Ă
6" and "X
Ă
7" as well as the
connection cables to the sensors for
damage.
Check the interconnecting cable connections
to all other external connections.
Possibly remove plug connections.
Internal fault on VRĂ20 PCB Replace theĂVRĂ20 PCB
AD converter faulty ć burner
control unit
Replace the PCB on the LGM
Ă
29 burner
control unitĂ
Fault because of a temporary
on-site power failure
Press reset keyĂ" EU " once
Air pressure sensor
Cable break
Check wiring
Air pressure sensor
Short circuit
Replace sensor
5692Ă485
G
B