Gree FGR20Pd/DNa-X Owner's Manual page 12

2.3.2 Drainage Pipe Installation
For easy drainage of the condensation water, the drainage pipe should be
installed with a downward gradient. To avoid the condensation, the connection pipe
joint should be insulated with thermal insulation material. A water seal should be
employed as shown in Fig.8 and the height of the water seal could be determined
by the pressure of the drain hose.
Drain hose is in negative pressure state: A = B≥P/10+20 (mm).
Drain hose is in positive pressure state: A≥30mm，B≥P/10+20 (mm).
NOTE: P is the absolute pressure of the drain hose position, Pa.
Ducted Type Split Air-Conditioner Units(Inverter Series)
Fig.7
Fig.8
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