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Installation Instructions
Bosch IDS BOVB20 Split System Heat Pump - BTC 761701316 C (02.2022)
WARNING: HAZARDOUS VOLTAGE
When measuring resistance , make sure the unit is powered
off and wait 3 min before taking measurement.
Figure 65
P1/F1 (High pressure protection)
Are you running in
force mode?
Quit force mode
Clear any blockage in
refrigerant,correct poor
heat exchange (air flow
restriction, motor failure)
Restart system
Are the
service valves open?
Open the service valves
Adjust refrigerant
Is the
high pressure switch
wired correctly and resistance
≥1Ω?
Replace high
pressure switch
Yes
No
No
Yes
Is the
ambient temperature
>120°F ?
No
Yes
Yes
Is there
abnormal pressure
in the system?
No
Yes
Is the system
overcharged?
Yes
No
No
Figure 66
P2 (Low pressure protection)
H5 (System lockout, P2 occurs 5 times in 100 minutes)
Restart system
Are the
service valves open?
Open the service valves
Is the
system undercharged?
Adjust refrigerant
Replace pressure
transducer
Is there
abnormal pressure in the
system?
Clear any blockage in the
refrigerant,Correct poor
heat exchange (air flow
restriction, motor failure)
Yes
No
Yes
No
Yes
No
No
Yes
Run
unit in cooling
or heating mode. Is the
suction pressure within 50 PSI
of checkpoint No.9
(cooling) or No.10
(heating)?