Viessmann Vitoclima 300-S Service Instructions For Contractors page 19

Diagnosis
(cont.)
A Fault LEDs
B Equipment LED external unit
C Equipment LED internal device A
D Equipment LED internal device B
Note
Only one fault code will be displayed, even if several faults have occurred.
To display further fault codes:
Switch the unit OFF and isolate it from the power supply.
Remove the fault.
Call up the diagnostic function again.
Fault codes external unit, type OD306H
No. Fault code
5 4 3 2
01
02
03
04
The standby LED illuminates as soon
as the device is switched ON.
The equipment LEDs illuminate in
sequence, and the respective fault
code is indicated by the 5 fault LEDs.
If there is no fault, the equipment LED
with the corresponding status illumi-
nates for 5 s and then changes to the
next equipment LED.
If a fault occurs at the equipment, the
relevant equipment LED illuminates
for 10 s. At the same time, the fault
code is displayed by the fault LEDs.
Fault
1
Temperature sensor of
the heat exchanger of
the external unit not
connected
Short circuit of the
temperature sensor of
the heat exchanger of
the external unit
Compressor tempera-
ture sensor not con-
nected
Compressor tempera-
ture sensor short cir-
cuit
Troubleshooting
Cause/Remedy
Check sensor connection;
replace sensor
Check sensor connection;
replace sensor
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