Viessmann Vitocal 300-G Installation And Service Instructions Manual page 121

Control unit diagnostics
ID Message
(priority)
05 Fault EEV ("U") 1.
07 Message EEV
("i")
10 Outside temp.
sensor ("U")
18 Outside temp.
sensor ("U")
20 Flow sens.
sec. ("U")
21 Return sens.
sec. ("U")
28 Flow sens.
sec. ("U")
29 Return sens.
sec. ("U")
30 Flow sens. pri-
mary ("U")
31 Return sens.
primary ("U")
(cont.)
1. Cause
2. Measures
Fault message from the EEV :
Refrigerant circuit control
2. The system must be reconfigured
1. Message from the EEV: Refrigerant
circuit control
2. No measures required
1. Outside temperature sensor shorted
out
2. Check the sensor and replace, if
required
1. Outside temperature sensor lead
broken
2. Check the sensor and replace, if
required
1. Short circuit, secondary flow tem-
perature sensor
2. Check the sensor and replace, if
required
1. Short circuit, secondary return tem-
perature sensor
2. Check the sensor and replace, if
required
1. Break, secondary flow temperature
sensor
2. Check the sensor and replace, if
required
1. Break, secondary return temperature
sensor
2. Check the sensor and replace, if
required
1. Short circuit, primary flow tempera-
ture sensor (IN)
2. Check the sensor and replace, if
required
1. Short circuit, primary return tempera-
ture sensor (OUT)
2. Check the sensor and replace, if
required
Troubleshooting
Access
right
Customer
Heating en-
gineer
Customer
Customer
Customer
Customer
Customer
Customer
Customer
Customer
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