Hi to everybody - I am new to this forum so be kind!

I have a split inverter heat pump system made by VS AIR, model is vsw-h12b4/sd when turned on the internal unit fan runs in cooling mode, not in heat mode though.

Outside unit does not fire up at all although voltages are present on power and control boards, 300v for compressor 12v 8v aqnd 5v for control.

After several minutes inside unit stops and displays F6.

I disconnected comms line to outside unit and got error code E5 so both units appear to be talking to each other.

Any help / advice greatly appreciated

Thanks