Bosch IDS BOVA15 Installation Instructions Manual page 31

H8 (Pressure transducer (PT) fault)
Is the pressure
transducer (PT) connected
correctly
Yes
Run
unit in cooling
or heating mode. Is the
suction pressure within 50 PSI
of checkpoint No.9
(cooling) or No.10
(heating)?
Yes
Did the control board fail?
No
Restart system
Figure 49
Bosch IDS BOVA15 Split System Heat Pump - BTC 761701317 A (02.2022)
No Correct wiring
Replace pressure
No
transducer
Replace control board
Yes
WARNING: HAZARDOUS VOLTAGE

When measuring resistance , make sure the unit is powered
off and wait 3 min before taking measurement.
P0 (Control board is over-heated)
Is
there dust or
debris blocking the
Yes
control board heat
sink?
No
Did the outdoor
fan motor fail?
No
Are
the screws
properly installed and/
or is there enough
silicone grease?
Yes
Did the control
board fail?
No
Restart system
Figure 50
Installation Instructions
Refer to control board
replacement instructions to
ensure there is good contact
between the heat sink
and control board. Ensure
there is no debris
blocking the radiator.
Replace motor
Yes
Tighten the screws and/or
No
apply silicone grease
Yes Replace control board
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