Bosch 15 SEER2 Series Installation Instructions Manual page 35

Error Code Description
PH Low discharge super heat protection
P0 High module radiator temperature (TF) protection
Table 24
Figure 37
P0 (High module radiator temperature (TF) protection)
Diagnosis
Check whether there is
dust or fallen leaves
influencing the radiator
No
Check whether the Tf is
normal according to Table
37 (between temperature
and resistance)
Yes
Restart system and check
whether the fan and motor
can operate normally
Yes
Operate system and check
whether there`s the same fault
Yes
Figure 38
Bosch 15 SEER2 Inverter Ducted Packaged Heat Pump - BTC 761701319 A (12.2022)
Handling
Yes
Clean all the dust
and fallen leaves
No
Replace Tf sensor
or Control Board
No
Replace the fan and motor
No
Operate normally
Error Code Description
P2 Low pressure (PT) Protection in cooling and heating
System lockup, 5 times (P2) protection in 100
H5
minutes
P4 High compressor discharge temperature(T5)
Table 25
P2 (Low pressure (PT) Protection in cooling)
H5 (System lockup, 5 times (P2) protection in 100 minutes)
Diagnosis
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 8th or 11th
data of check when cooling.
Yes
Figure 39
P4 (High compressor discharge temperature (T5) protection)
Diagnosis
Check whether the T5 is normal
according to Table 37 (between
temperature and resistance)
Yes
Check whether the charge is
correct by subcooling
according to installation guide
in charge mode when cooling
No
Check whether the
compressor is normal
(abnormal noise,abnormal
vibration)
Yes
Check whether the EEV is
normal for throttle when
heating (wire seated .coil)
Yes
Figure 40
Installation Instructions
Handling
Exclude indoor unit
No
fault reasons and
restart
No
Adjust the charge
No Replace the pressure
transducer
Handling
No
Replace the T5 sensor
Yes
Adjust the charge
No
Replace the compressor
Re-power and check
No
again,if the same, replace
the EEV.
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