5520 - Bosch Heat Pump Z2 low pressure warning JR0

What does 5520 mean?

This warning indicates low pressure (JR0) in Bosch Heat Pump zone 2. It triggers if sensor PL1 is below the lowest permitted actual envelope (-27°C) for longer than 30 seconds.

• The outdoor fan is not working.
• The outdoor fan is not receiving 230V power.
• A fault with the I/O board.

Click steps to track your progress.

1. 1

   Activate the 'test outdoor unit' function in your Heat Pump's settings or app.

2. 2

   Ensure there are no physical obstructions like debris or ice blocking the outdoor fan.

3. 3

   If the fan does not operate, contact a qualified technician to check the fan's power supply and the I/O board.