Viessmann Vitoclima 300-S Service Instructions For Contractors page 24

Troubleshooting
Diagnosis
(cont.)
Fault Fault
code
22 Min. compressor speed not
achieved
23 System configuration changed
24 Problem with system configura-
tion
25 Overtemperature cut-out cool-
ing block (compressor is
switched OFF)
26 Protection against icing-up
27 Overtemperature cut-out com-
pressor (compressor is
switched OFF)
28 System overload protection
(compressor is switched OFF)
29 EEPROM faulty
30 Not configured (controller can-
not be started)
31 Poor transmission quality
Note
Procedure for testing the most impor-
tant components on page 28.
24
Cause/Remedy
Restart; if problem persists, re-
place controller of the external
unit
For information only (communi-
cation cables were modified)
Incorrect internal device con-
nected;
the total output of the internal de-
vices is greater than the max.
output of the external unit;
modify the configuration, if re-
quired
Air inlet blocked; check external
fan motor
No fault; protection against icing-
up is active during defrosting
Check whether there is insuffi-
cient refrigerant
No measure required; compres-
sor delay (approx. 2 h)
Restart; replace controller, if EE-
PROM is required (operation with
specific parameters)
Restart; if problem persists, re-
place controller
Check the connecting cable be-
tween the internal device, the ex-
ternal unit and earth