How do I purge the solar circuit of a Spring panel?

Fill each line of panels separately by installing valves on the interline fittings in order to purge the air efficiently.
Make sure that the pump is unplugged or switched to OFF. Turn the blue and red ball valves upright

Check the watertightness of the circuit.

Fill with glycol and rotate the filling pump for 30 minutes at a pressure lower than the maximum pressure given in the table given below.

During this time, purge so that the fluid exits without air bubbles, using the manual drain and the water hammer action of repeatedly closing/opening the drain valve.