Panasonic U-5MX4XPQ, Installation Manual

Installation manual

15

U-5~18MX4XPQ

Urban Multi air conditioner

4PW28163-1

8.9.

Wiring example for wiring inside unit

See figure 26.

9.

P

IPE

INSULATION

After finishing the leak test and vacuum drying, the piping must be
insulated. Take into account the following points:

■

Make sure to insulate the connection piping and refrigerant
branch kits entirely.

■

Be sure to insulate liquid and gas piping (for all units).

■

Use heat resistant polyethylene foam which can withstand a
temperature of 70°C for liquid side piping and polyethylene foam
which can withstand a temperature of 120°C for gas side piping.

■

Reinforce the insulation on the refrigerant piping according to
the installation environment.

Condensation might form on the surface of the insulation.

■

If there is a possibility that condensation on the stop valve might
drip down into the indoor unit through gaps in the insulation and
piping because the outdoor unit is located higher than the indoor
unit this must be prevented by sealing up the connections. See
figure 9.

10. C

HECKING

OF

UNIT

AND

INSTALLATION

CONDITIONS

Be sure to check the following:

The piping work

1

Make sure piping size is correct.

See "6.2. Selection of piping material" on page 5.

2

Make sure insulation work is done.

See "9. Pipe insulation" on page 15.

3

Make sure there is no faulty refrigerant piping.

See "6. Refrigerant piping" on page 4.

The electrical work

1

Make sure there is no faulty power wiring or loose nuts.

See "8. Field wiring" on page 10.

2

Make sure there is no faulty transmission wiring or loose nuts.

See "8. Field wiring" on page 10.

3

Make sure the insulation resistance of the main power circuit is
not deteriorated.

Using a megatester for 500 

V, check that the insulation

resistance of 2 M

Ω

 or more is attained by applying a voltage of

500 V DC between the power terminals and earth. Never use
the megatester for the transmission wiring (between outdoor
and indoor unit, outdoor and COOL/HEAT selector, etc.).

Precautions when laying power wiring

■

Do not connect wiring of different thicknesses to the
power terminal block. (Slack in the power wiring may
cause abnormal heat.)

■

When connecting wiring which is the same thickness,
do as shown in the figure below.

■

For wiring, use the designated power wire and
connect firmly, then secure to prevent outside
pressure being exerted on the terminal board.

■

Use an appropriate screwdriver for tightening the
terminal screws. A screwdriver with a small head will
strip the head and make proper tightening impossible.

■

Over-tightening the terminal screws may break them.

■

See the table below for tightening torque for the
terminal screws.

Recommendations when connecting the ground

When pulling the ground wire out, wire it so that it comes
through the cut out section of the cup washer. (An
improper ground connection may prevent a good ground
from being achieved.) (See figure 21)

1

Electric wiring

2

Wiring between units

3

Clamp to the electric box with field supplied clamps.

4

When routing out the power/ground wires from the right side:

5

When routing the remote control cord and inter-unit wiring, secure 
clearance of 50 mm or more from the power wiring. Ensure that 
the power wiring does not contact any heated sections ( 

 ).

6

Clamp to the back of the column support with field supplied 
clamps.

7

When routing out the inter-unit wirings from the opening for piping:

8

When routing out the power/ground wires from the front:

9

When routing out the ground wires from the left side:

10

Grounding wire

11

When wiring, pay attention not to detach the acoustic insulators 
from the compressor.

12

Power supply

13

Fuse

14

Earth leakage breaker

15

Ground wire

16

Unit A

17

Unit B

18

Unit C

Tightening torque (N•m)

M8 (Power terminal block)

5.5~7.3

M8 (Ground)

M3 (Inter-unit wiring terminal block)

0.8~0.97

Ambient temperature

Humidity

Minimum thickness

≤

30°C

75% to 80% RH

15 mm

>30°C

≥

80 RH

20 mm

1

Gas line stop valve

2

Liquid line stop valve

3

Service port for adding refrigerant

4

Sealing up treatment

5

Insulation

6

Indoor -outdoor interconnection piping

Be sure to insulate local pipes, as touching them can
cause burns.