Effect of Liquid Subcooling:

This is always desirable to sub cool the refrigerant before throttling. This influenced is illustrated in the following Figure (Figure 8(a) & 8(b)).

It is illustrate from these two figures that the refrigeration effect is enhanced by an area under the procedure 5'-5.

Usually the magnitude of sub cooling is kept among 5 to 10 K. If there is too much sub cooling, then the work input enhanced considerably, therefore offsetting the advantage from the sub cooling of the refrigerant.

(a)                                                                (b)

Effect of Condensate Subcooling on COP