Viessmann VITOTRONIC 200 Service Instructions Manual page 161

Refrigerant circuit
(cont.)
Message Meaning
code
3A Safety high pressure
S
switch has responded.
43 Short circuit/lead break,
S
temperature sensor, refrig-
erant circuit controller
44 Short circuit/lead break,
S
secondary circuit flow
temperature sensor (up-
stream of instantaneous
heating water heater)
46 Short circuit/lead break,
S
liquid gas temperature
sensor
47 Short circuit/lead break,
S
reversible suction gas
temperature sensor
48 Suction gas superheating
―
too low
49 Evaporator max. operating
―
pressure (MOP) has been
reached; changeover from
superheating to pressure
control of the suction gas.
4C Suction gas superheating
―
too high
55 Too little refrigerant
H
Heat pump characteris-
tics
Compressor OFF
Compressor OFF
Compressor OFF
Compressor OFF
Compressor OFF
Compressor OFF
Compressor remains in op-
eration.
Compressor OFF
Compressor OFF
Measure
As for "C9 Refrigerant circ (SHD)":
See "Message overview" for the heat
pump control unit.
Check resistance value (NTC 10 k
at connection J21 (T2) of the EEV
PCB: See "EEV PCB [4-3] / [4-4]".
Vitocal 200-A/222-A:
■
Check resistance value (NTC 10 k
at connection J21 (T1) of the EEV
PCB: See "EEV PCB [4-3] / [4-4]".
Vitocal 200-S/222-S:
■
Check resistance value (Pt500A) at
connection X25.3/X25.4 of the con-
troller and sensor PCB: See "Con-
troller and sensor PCB".
Vitocal 200-A/222-A:
■
Check resistance value (NTC 10 k
at connection J21 (T3) of the EEV
PCB: See "EEV PCB [4-3] / [4-4]".
Vitocal 200-S/222-S:
■
Check resistance value (Pt500A) at
connection F25 (X25.17/X25.18) of
the controller and sensor PCB: See
"Controller and sensor PCB".
Check resistance value (Pt500A) at
connection X25.15/X25.16 of the con-
troller and sensor PCB: See "Control-
ler and sensor PCB".
Check whether the correct coding
■
card is fitted. To check information,
see "System information".
In the event of recurrence: Have the
■
refrigerant circuit checked by a re-
frigeration engineer.
No action required
Check whether the correct coding
■
card is fitted. To check information,
see "System information".
In the event of recurrence: Have the
■
refrigerant circuit checked by a re-
frigeration engineer.
Check amount of refrigerant. Adjust
the amount of refrigerant if necessary.
Diagnosis
)
Ω
)
Ω
)
Ω
161