Bosch IDS BOVB60-20 - Troubleshooting Fault Codes H8 and PO

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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
Figure 63
H8 (Pressure transducer (PT) fault)
Did the control board fail? Replace control board
Correct wiring
Restart system
Replace pressure
transducer
Is the pressure
transducer (PT) wired
correctly?
Yes
No
Yes
No
Yes
No
Run
unit in cooling
or heating mode. Is the
suction pressure within 50 PSI
of checkpoint No.9
(cooling) or No.10
(heating)?
WARNING: HAZARDOUS VOLTAGE
 When measuring resistance , make sure the unit is powered
off and wait 3 min before taking measurement.
Figure 64
P0 (Control board is over-heated)
Did the outdoor
fan motor fail?
Refer to control board
replacement instructions to
ensure there is good contact
between the heat sink
and control board
Replace motor
Replace Tf sensor
Replace control board
Restart system
Is there poor heat
dissipation?
Yes
No
Yes
Yes
No
No
No
Yes
Yes
No
Correct T5 and Tf
connections
Are T5 and
Tf connections at
control board
correct?
Is the
resistance of
Tf in the range of
Table 16?
Did the control
board fail?