10
6.
Refrigerant piping w
ork
6.1.Refrigerant pipe
[Fig. 6-1] (P
.3)
a
Indoor unit
b
Outdoor unit
Ref
er to the Instruction Man
ual that came with the outdoor unit for the restrictions on
the height difference betw
een units and for the amount of additional refr
igerant
charge
.
Avoid the f
ollowing places f
or installation where air conditioner trouble is liab
le to
occur.
•
Where there is too much oil such as f
or machine or cooking.
•
Salty environment as seaside areas
.
•
Hot-spring areas
.
•
Where sulfide gas exists
.
•
Other special atmospheric areas
.
•
This unit has flared connections on both indoor and outdoor sides.
[Fig. 6-1]
•
Refriger
ant pipes are used to connect the indoor and outdoor units as shown in the
figure below
.
•
Insulate both refrigerant and drainage piping completely to pre
vent condensation.
Piping preparation
•
Refriger
ant pipes of 3, 5, 7, 10 and 15 m [9-13/16, 16-3/8, 22-15/16, 32-1/4 and 49-
3/16 ft] are available as optional items
.
(1)T
able belo
w shows the specifications of pipes commercially a
vailab
le.
(2)Ensure that the 2 refr
igerant pipes are w
ell insulated to prevent condensation.
(3)Refr
igerant pipe bending radius must be 10 cm [3-15/16 in] or more
.
Caution:
Using careful insulation of specified thickness.
Excessive thickness pre
vents
storag
e behind the indoor unit and smaller thickness causes de
w drippag
e.
6.2.Flaring w
ork
•
Main cause of gas leakage is defect in flar
ing work.
Carry out correct flar
ing wor
k in the follo
wing procedure.
6.2.1.
Pipe cutting
[Fig. 6-3] (P
.3)
a
Copper tubes
b
Good
c
No good
d
Tilted
e
Uneven
f
Burred
•
Using a pipe cutter cut the copper tube correctly .
6.2.2.
Burrs remo
val
[Fig. 6-4] (P
.3)
a
Burr
b
Copper tube/pipe
c
Spare reamer
d
Pipe cutter
•
Completely remove all burrs from the cut cross section of pipe/tube.
•
Put the end of the copper tube/pipe to downw
ard direction as you remo
ve b
urrs in
order to avoid b
urrs drop in the tubing.
6.2.3.
Putting nut on
[Fig. 6-5] (P
.3)
a
Flare nut
b
Copper tube
•
Remove flare n
uts attached to indoor and outdoor unit, then put them on pipe/tube
having completed b
urr removal.
(not possible to put them on after flar
ing work)
6.2.4.
Flaring work
[Fig. 6-6] (P
.3)
a
Flaring tool
b
Die
c
Copper tube
d
Flare nut
e
Y ok
e
•
Carry out flaring wor
k using flaring tool as sho
wn below
.
Dimension
Pipe diameter
A (mm [in])
(mm [in])
When the tool for R410A is used
B (mm [in])
Clutch type
6.35 [1/4]
0 to 0.5 [0 to 1/32]
9.1 [3/8]
9.52 [3/8]
0 to 0.5 [0 to 1/32]
13.2 [17/32]
12.7 [1/2]
0 to 0.5 [0 to 1/32]
16.6 [21/32]
15.88 [5/8]
0 to 0.5 [0 to 1/32]
19.7 [25/32]
Firmly hold copper tube in a die in the dimension sho
wn in the table at abo
ve
.
6.2.5.
Check
[Fig. 6-7] (P
.3)
a
Smooth all around
f
Scratch on flared plane
b
Inside is shining without any scr
atches
g
Crack
ed
c
Even length all around
h
Unev
en
d
T oo much
i
Bad examples
e
Tilted
•
Compare the flared wor
k with a figure in right side hand.
•
If flare is noted to be defectiv
e, cut off the flared section and do flar
ing work again.
6.3.Pipe connection
[Fig. 6-8] (P
.3)
•
Apply a thin coat of refrigeration oil on the seat surface of pipe
.
•
For connection first align the center
, then tighten the first 3 to 4 turns of flare n
ut.
•
Use tightening torque table belo
w as a guideline for indoor unit side union joint section,
and tighten using two wrenches
. Excessiv
e tightening damages the flare section.
Copper pipe O.D
.
Flare nut O
.D.
Tightening torque
(mm [in])
(mm [in])
(N·m)
ø6.35 [1/4]
17 [11/16]
14 - 18
ø9.52 [3/8]
22 [7/8]
34 - 42
ø12.7 [1/2]
26 [1-1/32]
49 - 61
ø15.88 [5/8]
29 [1-5/32]
68 - 82
W
arning:
Be careful of flying flare n
ut! (Internally pressurized)
Remove the flare n
ut as follo
ws:
1.
Loosen the nut until you hear a hissing noise
.
2.
Do not remove the n
ut until the gas has been completely released (i.e
., hiss-
ing noise stops).
3.
Check that the gas has been completel
y released, and then remo
ve the nut.
Outdoor unit connection
Connect pipes to stop valv
e pipe joint of the outdoor unit in the same manner applied
for indoor unit.
•
For tightening use a torque wrench or spanner
, and use the same tightening torque
applied for indoor unit.
Pipe
For liquid
For gas
For liquid
For gas
For liquid
For gas
For liquid
For gas
Outside diameter
mm
inch
9.52
3/8
15.88
5/8
9.52
3/8
15.88
5/8
9.52
3/8
15.88
5/8
9.52
3/8
15.88
5/8
Model
PEAD-
A24AA4
PEAD-
A30AA4
PEAD-
A36AA4
PEAD-
A42AA4
Insulation
material
Heat resisting
foam plastic
0.045 specific
gravity
Insulation thickness
mm
inch
8
5/16
8
5/16
8
5/16
8
5/16
8
5/16
8
5/16
8
5/16
8
5/16
Min wall thic
kness
mm
inch
0.8
1/32
1.0
1/32
0.8
1/32
1.0
1/32
0.8
1/32
1.0
1/32
0.8
1/32
1.0
1/32
+0
-0.4 [-1/32]
WT06034X01_GB.p65
10.8.30, 17:06
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