Bosch BOVB 18 Series Installation Instructions Manual page 34

3 4 | Bosch IDS BOVB 18
F1 (High pressure switch (HPS) fault)
Diagnosis
Check whether the service
valves are open
Yes
Check whether high pressure
switch (HPS) wiring is seated
and normal
Yes
Check whether the
resistance of HPS is close to
0KΩ
Yes
Check whether there is the
same fault
Yes
Figure 55
Error Code Description
C3 Condenser coil sensor (T3) is seated fault in cooling
E7 Compressor discharge sensor (T5) is seated fault
Table 19
C3 Condenser coil sensor (T3) is seated fault in cooling)
Diagnosis
Check whether condenser
coil sensor (T3) is seated
to the condenser coil
Yes
Check whether the T3/T4
sensors are connected
according to wiring diagram
Yes
Check whether the
resistance of T3/T4 is in
the range of Table 24
Yes
Check whether there are
other heat sources around
T3/T4
Yes
Check whether there is the
same fault
Yes
Figure 56
Data subject to change
Handling
No
Open the service valve
No
Wiring according to the
diagram correctly
No
Replace high pressure
switch
No
Keep running
Handling
No
Reseat the sensor to
condenser coil
Wire according to the
No
wiring diagram correctly
No
Replace the fault
T3/T4 sensor
No
Remove all the other
heat sources
No
Keep running
E7 Compressor discharge sensor (T5) is seated fault)
Diagnosis
Check whether compressor
discharge sensor (T5) is
seated to the compressor
discharge line
Yes
Check whether the sensor of
T3/T5 are connected accord-
ing to wiring diagram
Yes
Check whether the resistance
of T3/T5 is in the range of
Table 27 and Table 25
Yes
Check whether there are other
heat sources around T3/T5
Yes
Check whether there is the
same fault
Figure 57
Error Code Description
E6 DC fan motor fault (for 48K/60K model)
Table 20
If the E6 error code appears occasionally, no action is necessary. The system will
restart automatically after 6 minutes.
E6 DC fan motor fault)
Diagnosis
Check whether DC motor
wiring is reliably connected
according to the wiring
diagram
Yes
Check whether outdoor
coil air return is blocked
Yes
Check whether there is
15V DC between the test
point P & N
Yes
Check whether there is
the same fault
Yes
Figure 58
Installation Instructions
Handling
No
Reseat the sensor to
discharge tube
No Wire according to the
wiring diagram correctly
No
Replace the fault T3/T5 sensor
No
Remove all the other
heat sources
No
Keep running
Handling
Reseat the wiring
No
according to
wiring diagram
No
Remove all the barriers
No
Replace the control board
No
Keep running
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