Page 149 - Defrosting for Air Source Heat Pump

142 Defrosting for Air Source Heat Pump

Fig. 5.19 Airside surface conditions of the outdoor coil during defrosting in Case 1 (eight
photographs).

the water-collecting tray. Therefore, from 60 to 80 s, there were few melted frost drops
downward flowing away from the circuit. In addition, as shown in Fig. 5.19,atthe
places indicated by the white arrows, a lot of melted frost kept downward flowing
to the water-collecting tray for about 60 s, from 80 to 140 s. It is very obvious that
at 100 s into defrosting, there was a lot of melted frost flowing away from the circuit.
The melted frost downward flowed away from these circuits, reduced the energy
consumption on vaporizing, and improved defrosting performance.