The flashing red dot (LED) indicates the Sanden heat pump unit is currently in 'sleep mode', it is perfectly normal and nothing to worry about.
We consider this the "Sanden Heart Beat". If you see a red flashing dot, the heart is beating and all is well for your Sanden heat pump.
This controller display with the red flashing dot is applicable to the following Sanden heat pump models:
Sanden G3 - "GS3-45HPA-AU"
Sanden G4 - "GAU-A45HPC"
Sanden G5 - "GAU-A45HPD"
