Viessmann VITOCAL 300-A Installation And Service Instructions Manual page 118

Troubleshooting
Control unit diagnostics
4. "Message history".
5. "TIME" for the times at which
the messages
occurred.
Message overview
As an identifier, all messages have a two-digit number.
Message
U01 System fault
!02 Std after data err
!03 Configuration fault
U05 Fault EEV
¸07 Message EEV
U10 Outside temp. sen-
sor
U18 Outside temp. sen-
sor
118
(cont.)
6. "MESSAG" to return to the mes-
Ó Time information relates to the
time at which the message
occurred.
Ò Time information relates to the
time at which the message was
deleted or the fault was remedied.
Cause
Control unit processor
faulty
Delivered condition set
after recognition of the
data fault
Incorrect configuration
of system components
Refrigerant circuit con-
trol fault message (con-
troller for electronic
expansion valve EEV)
Refrigerant circuit con-
trol message (controller
for electronic expansion
valve EEV)
Short circuit, outside
temperature sensor
Break, outside tempera-
ture sensor
sage display.
Measures
Replace the programming
unit
Reconfigure the system
Set delivered condition
("Reset", see operating
instructions) and reconfi-
gure the system
Observe messages in heat
pump module diagnosis
(see page 126)
No measures required
Check the sensor and re-
place if required (see
page 164 and 173)
Check the sensor and re-
place if required (see
page 164 and 173)