Hb ( High Pressure(Pt) Protection In Heating); P0 (High Module Radiator Temperature (Tf)Protection); P3 ( Compressor Over Current Protection) - Bosch BOVA Series Installation Instructions Manual

Installation Instructions

Hb ( High pressure(PT) protection in Heating)

Diagnosis
Check whether the service
valves are open
Yes
Check whether indoor unit is
normal by filter and airflow
Yes
Check whether indoor air inlet
temp. is over 86°F
No
Restart system and check
whether EEV is working
Yes
Make a comparison between
the pressure gauge and the
read from check data
Yes
Figure 47

P3 ( Compressor over current protection)

Diagnosis
Check whether the service
valves are open
Yes
Check whether outdoor unit
motor is abnormal and the
outdoor condenser coil is
blocked
No
Check whether compressor
wiring is normal
Yes
Check whether compressor
insulation resistance is greater
than 100KΩ
Yes
Restart system and check whether
the difference of high and low
pressure is more than 30 PSI after
compressor running 10 min
No
Check whether the
compressor current is more
than 18A when protection
Yes
Figure 48
Bosch Thermotechnology Corp. | 12.2016
Handling
No
Open the service valve
No
Exclude indoor unit fault
reasons and restart
Remove e.g. indoor side
Yes
E-heater or other heat
sources
No
Reseat the EEV throttle
No
Reseat or replace the
PT sensor
Handling
No
Open the service valve
Yes Replace the fan or
remove all the barriers
No
Wiring correctly according to
the wiring diagram
No
Replace compressor
Yes
Replace compressor
No
Replace the board
Replace the compressor
Error Code Description
P0 High module radiator temperature (TF) protection
Table 15

P0 (High module radiator temperature (TF)protection)

Diagnosis
Check whether there`s dust or
fallen leaves influencing
radiator
No
Check whether the Tf is
normal according to Table
2(between temperature and
resistance)
Yes
Restart system and check
whether the fan and motor
can normally operate
Yes
Operate system and check
whether there`s the same fault
Yes
Figure 49
Error Code Description
P2 Low pressure(PT) Protection in cooling
H5 System lockup, 5 times (P2) protection in 100 minutes
P4 High compressor discharge temperature(T5) protection
Table 16
P2 ( Low pressure(PT) Protection in cooling)
H5 ( System lockup, 5 times (P2) protection in 100 minutes)
Diagnosis
Check whether the service
valves are open
Yes
Check whether indoor unit is
normal by valve, filter, airflow
and throttle
Yes
Check whether the charge is
correct by subcooling
according to installation guide
in charge mode when cooling
Yes
Check whether the pressure
transduce is measuring
properly from the 8 th or 11
data of check when cooling
Yes
Figure 50
Bosch IDS BOVA | 29
Handling
Clean all the dust
Yes
and fallen leaves
No
Replace Tf sensor
No
Replace the fan and motor
No
Operate normally
Handling
No
Open the service valve
Exclude indoor unit
No
fault reasons and
restart
No
Adjust the charge
No
Replace the pressure
th transducer
Data subject to change