(C) Subcooling in the condenser by ensuring that a part of it is
flooded by liquid. This solution corresponds to a very simple
architecture but is also the most difficult to control: the
refrigerant charge must be exactly adapted to the required
subcooling (too much refrigerant in the cycle entails a larger
liquid zone in the condenser and therefore excessive subcooling)
and the operating conditions cannot vary since this
causes fluctuations of the liquid level.