Panasonic CS-Z25UB4EAW Service Manual page 41

Vacuum drying
After completing the piping connection, execute
vacuum drying for the connecting piping and the
indoor unit.
The vacuum drying must be carried out by using the
service ports of both the liquid and gas side valves.
CAUTION Use two wrenches and tighten with
regular torque.
12.1.5 Indoor Unit Drain Piping

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).

Drain piping must have down-slope (1/50 to 1/100); be sure not to provide up-and-down slope to prevent reversal
flow.

Be sure to check no air trap on drain hose and to ensure smooth water flow and no abnormal sound.
Indoor
unit
Pipe clamp
Down-slope

The height of drain may be possible up to
750 mm.
Down-slope
Air Trap
The air conditioner uses a drain up motor to drain water. Use the following procedure to test the drain
Drain Test
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.

Pour about 600-700cc of water in the drain pan of the indoor unit. (Pour from the position specified in the drawing
by using a water supply bottle or other suitable tool.)

Press the drain pump test run on pcb to start the drain motor, and verify water drainage.
(The drain motor will automatically stop after operating for about five minutes.)
Drain up motor
Upward routing
Trap
Upward-slope
No Air Trap
Drain hose
Feed water
Drain
port
Drain hose connection
Use the clip (accessory)
Do not overtighten, overtightening may cause gas leakage.
Piping size
6.35 mm (1/4")
9.52 mm (3/8")
12.7 mm (1/2")
15.88 mm (5/8")
19.05 mm (3/4")

When drain set piping, install as shown in the
figure below.
Indoor
unit
Down-slope (1/50 ~ 1/100)
Main drain pipe
Glue the joint
Drain pan
Air outlet vent
41
[18 N•m (1.8 kgf•cm)]
[42 N•m (4.3 kgf•cm)]
[55 N•m (5.6 kgf•cm)]
[65 N•m (6.6 kgf•cm)]
[100 N•m (10.2 kgf•cm)]
Drain port
Down-slope (1/50 ~ 1/100)
Indoor unit Elbow
Apply the head when connecting with the
confluence pipe. (about 100 mm)
Use VP30 or more for confluence
Torque
Elbow