Bosch 15 SEER2 Series Installation Instructions Manual page 37

Error Code Description
C3 Condenser coil sensor (T3) is seated fault in cooling
E7 Compressor discharge sensor (T5) is seated fault
Table 28
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 34
Yes
Check whether there are
other heat sources around
T3/T4
Yes
Check whether there is the
same fault
Yes
Figure 45
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 34 and Table 35
Yes
Check whether there are other
heat sources around T3/T5
Yes
Check whether there is the
same fault
Figure 46
Bosch 15 SEER2 Inverter Ducted Packaged Heat Pump - BTC 761701319 A (12.2022)
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
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
Error Code Description
E6 DC fan motor fault
Table 29
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 DC motor
insulation resistance is
greater than 100KΩ
YES
Check whether the resistance
of fan motor U2/V2/W2 are
normal
YES
Check whether there is the
same fault
YES
Replace the board and
check whether there is the
same fault.
YES
Figure 47
Installation Instructions
Handling
NO Reseat the wiring
according to
wiring diagram
NO
Remove all the barriers
NO
Replace the DC motor
NO
Replace the DC motor
NO
Keep running
NO
Keep running
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