Viessmann VITOTRONIC 200 Service Instructions Manual page 88

Troubleshooting
Diagnosis (service scans)
Line "I [–]"
Col- Explanation
umn
4
Protection functions for control of hot gas superheating (C/D)
C Characteristics of the external
unit:
"0" Standard mode, protection
function disabled.
"1" Compressor frequency is
reduced slowly.
"2" Compressor frequency will
not be reduced further.
"3" Compressor frequency will be
increased.
Line "Nload, f [–, Hz]"
Col- Explanation
umn
2
Standardised output demand, value range: 0 to 127 (≙ 0 to 100 %)
3 Current compressor frequency in Hz.
4 Set compressor frequency in Hz.
Line "n1, n2 [rpm]"
Col- Explanation
umn
2 Speed of fan 1 in rpm.
3 Speed of fan 2 in rpm (if installed).
4 Set fan stage:
"0" OFF
"1" Low speed
"2" Medium speed
Line "OAT, OMT, OCT [°C]"
Col- Explanation
umn
2 Air intake temperature, evaporator (OAT)
3 Evaporation temperature (OMT)
4 Refrigeration inlet temperature, evaporator (OCT)
88
(cont.)
D Cause:
"0" Standard mode.
"1" Set value for hot gas super-
heating cannot be achieved by
adjusting position of EEV
valve.
"3" High speed
"4" Max. speed