40
Message
code
Meaning
Heat pump characteris-
tics
Measure
31
H
Temperature differential
between evaporator and
condenser too high
Compressor OFF
Reduce set temperatures in the sec-
ondary circuit.
32
H
Temperature differential
between evaporator and
condenser too low
Compressor OFF
Increase set temperatures in the sec-
ondary circuit.
33
H
Min. return temperature
secondary circuit under-
shot
Compressor does not start. Raise the return temperature in the
secondary circuit, e.g. with an on-site
heat source.
35
H
Minimum suction gas tem-
perature undershot
Compressor OFF
Check amount of refrigerant. Top up
refrigerant if required.
Other measures such as
"D3 Low
pressure"
: See "Message overview"
for the heat pump control unit.
48
―
Suction gas superheating
too low
Compressor OFF
■
Check whether the correct coding
card is fitted. For scanning, see
"System information".
■
In the event of repeat occurrence:
Have the refrigerant circuit checked
by a refrigeration engineer.
49
―
Max. operating pressure
(MOP) for evaporator has
been reached. Change-
over from suction gas su-
perheating to pressure
control.
Compressor remains in op-
eration.
No action required
4B
S
■
EEV connecting cable
faulty
■
EEV stepper motor faul-
ty
Compressor OFF
■
Check EEV connecting cable and
replace if required.
■
Replace EEV.
4C
―
Suction gas superheating
too high
Compressor OFF
■
Check whether the correct coding
card is fitted. For scanning, see
"System information".
■
In the event of repeat occurrence:
Have the refrigerant circuit checked
by a refrigeration engineer.
Curves and parameters of the temperature and
pressure sensors
■
Temperature sensors: See page 80.
■
Pressure sensor: See page 81.
Brief scan
The following information can be called up:
■
Software versions
■
Connected components
1. Service menu:
Press
OK
+
å
simultaneously and hold for
approx. 4 s.
2. "Diagnosis"
3. "Brief scan"
Diagnosis
Refrigerant circuit
(cont.)
5800 917 GB
Diagnosis
