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11.5.5 INDOOR UNIT DRAIN PIPING
• Drain piping must have down-slope (1/50 to
1/100); be sure not to provide up-and-down slope
to prevent reversal flow.
• During drain piping connection, be careful not to
exert extra force on the drain port at the indoor
unit.
• The outside diameter of the drain connection at
the indoor unit is 32 mm.
Piping material: Polyvinyl chloride pipe VP-25 and
pipe fittings.
• Be sure to perform heat insulation on the drain
piping.
Heat insulation material: Polyethylene foam with
thickness more than 8 mm (local supply).
Upward routing
Pipe clamp
Indoor
unit
Trap
Down-slope
• The height of drain may be possible up to 750 mm.
Down-slope (1/50 ~ 1/100)
Drain port
750 mm or less
Indoor unit
Elbow
Elbow
• When drain set piping, install as shown in the
figure below.
Drain Test
The air conditioner uses a drain up motor to drain water. Use the following procedure to test the drain up motor
operation.
• Connect the main drain pipe to exterior and leave
it provisionally until the test comes to an end.
• Feed water to the flexible drain hose and check
the piping for leakage.
• Be sure to check the drain up motor for normal
operating and noise when electric wiring is
complete.
• When the test is complete, connect the flexible
drain hose to the drain port.
Feed water
Drain hose
Drain u