Bosch · Heat Pumps
This alarm indicates low evaporation pressure (JR0) in Bosch Heat Pump zone 1. It activates after 3 warnings in 3 hours, or if a warning is active for 30 minutes.
Click steps to track your progress.
If the Heat Pump was recently serviced or components replaced, contact your installer to verify the correct inverter/I/O board combination.
Ask your installer to check the setting of the rotary encoder on the I/O board against the system's wiring diagram.
Reset the Heat Pump by cycling its power at the main breaker.
If the alarm persists, a qualified technician should review the system's internal configurations and installed components.