1-96
1
1
(1) Apply a sealing cap or water-proof tape to prevent dust or
water from entering the tubes before they are used.
(2) Be sure to apply refrigerant lubricant (ether oil) to the
inside of the flare nut before making piping connections.
This is effective for reducing gas leaks. (Fig. 1- 36)
(3) For proper connection, align the union tube and flare tube
straight with each other, then screw on the flare nut lightly
at first to obtain a smooth match. (Fig. 1- 37)
(1) Tightly connect the indoor-side refrigerant tubing extended
from the wall with the outdoor-side tubing.
Because the pressure is approximately 1.6 times higher than
conventional refrigerant pressure, the use of ordinary flare
nuts (Type 1) or thin-walled tubes may result in tube rupture,
injury, or asphyxiation caused by refrigerant leakage.
(2) To fasten the flare nuts, apply specified torque.
Caution Before Connecting Tubes Tightly
Cautions During Brazing
Apply refrigerant lubricant.
Fig. 1- 36
Adjust the shape of the liquid tube using a tube bender
at the installation site and connect it to the liquid
tubing side valve using a flare.
Replace air inside the tube with nitrogen gas to prevent copper oxide film from forming during the
brazing process. (Oxygen, carbon dioxide and Freon are not acceptable.)
Use a reducing valve for the nitrogen cylinder.
When removing the flare nuts from the tubing connections,
or when tightening them after connecting the tubing, be sure
to use a torque wrench and a spanner. (Fig. 1- 38)
If the flare nuts are over-tightened, the flare may be damaged,
which could result in refrigerant leakage and cause injury or
asphyxiation to room occupants.
For the flare nuts at tubing connections, be sure to use the
flare nuts that were supplied with the unit, or else flare nuts
for R410A (Type 2). The refrigerant tubing that is used must
be of the correct wall thickness as shown in the table.
In order to prevent damage to the flare caused by
overtightening of the flare nuts, use the table as a guide
when tightening.
When tightening the flare nut on the liquid tube, use an
adjustable wrench with a nominal handle length of 200 mm.
Do not use agents intended to prevent the formation of oxide film.
These agents adversely affect the refrigerant and refrigerant oil, and may cause damage or malfunctions.
Do not allow the tubing to get too hot during brazing.
The nitrogen gas inside the tubing may overheat, causing refrigerant system valves to become damaged.
Therefore allow the tubing to cool when brazing.
2. Connecting Tubing Between Indoor and Outdoor Units
Indoor Unit Tubing Connection (
1
,
2
...
n-1
)
Indoor unit type
Gas tubing (mm)
Liquid tubing (mm)
200
ø25.4
ø9.52
250
ø25.4
ø12.7
Outdoor unit
Torque wrench
Spanner
Indoor unit
Fig. 1- 38
Tightening torque
(approximate)
14 – 18 N · m
{140 – 180
kgf
· cm}
34 – 42 N · m
{340 – 420
kgf
· cm}
49 – 61 N · m
{490 – 610
kgf
· cm}
68 – 82 N · m
{680 – 820
kgf
· cm}
Tube
diameter
ø6.35 (1/4")
ø9.52 (3/8")
ø12.7 (1/2")
ø15.88 (5/8")
ø19.05 (3/4")
100 – 120 N · m
{1000 – 1200
kgf
· cm}
Tube
thickness
0.8 mm
0.8 mm
0.8 mm
1.0 mm
1.0 mm
Flare nut
Union
Fig. 1- 37
3. Insulating the Refrigerant Tubing
Tubing Insulation
Thermal insulation must be applied to all units tubing,
including distribution joint (field supply).
* For gas tubing, the insulation material must be heat
resistant to 120°C or above.
For other tubing, it must be resistant to 120°C or above.
For other tubing, it must be heat resistant to 80°C or above.
Insulation material thickness must be 10 mm or greater.
If the conditions inside the ceiling exceed DB 30°C and
RH 70%, increase the thickness of the gas tubing
insulation material by 1 step.
Two tubes arranged together
Liquid tubing
Gas tubing
Insulation
Fig. 1- 39
If the exterior of the outdoor unit valves has been
finished with a square duct covering, make sure you
allow sufficient space to access the valves and to
allow the panels to be attached and removed.
Taping the flare nuts
Wind the white insulation tape around the flare nuts at the gas tube connections.
Then cover up the tubing connections with the flare insulator, and fill the gap at the
union with the supplied black insulation tape.
Finally, fasten the insulator at both ends with the supplied vinyl clamps. (Fig. 1- 40)
WARNING
WARNING
Flare insulator (supplied)
Insulation tape
(white)(supplied)
Tube insulator
(not supplied)
Heat resistant
120°C or above
Flare union
Flare nut
Unit side
Fig. 1- 40
Insulation material
The material used for insulation must have good insulation characteristics, be easy to use, be age resistant,
and must not easily absorb moisture.
After a tube has been insulated, never try to bend it into a narrow curve because
it can cause the tube to break or crack.
Never grasp the drain or refrigerant connecting outlets when moving the unit.
4. Taping the Tubes
(1) At this time, the refrigerant tubes (and electrical wiring
if local codes permit) should be taped together with
armoring tape in 1 bundle. To prevent condensation
from overflowing the drain pan, keep the drain hose
separate from the refrigerant tubing.
(2) Wrap the armoring tape from the bottom of the outdoor
unit to the top of the tubing where it enters the wall.
As you wrap the tubing, overlap half of each previous
tape turn.
(3) Clamp the tubing bundle to the wall, using 1 clamp
approx. each meter. (Fig. 1- 41)
Fig. 1- 41
NOTE
Do not wind the armoring tape too tightly since this will
decrease the heat insulation effect.
Also ensure that the condensation drain hose splits away
from the bundle and drips clear of the unit and the tubing.
5. Finishing the Installation
After finishing insulating and taping over the tubing, use sealing putty to seal
off the hole in the wall to prevent rain and draft from entering. (Fig. 1- 42)
Apply putty here
Tubing
Fig. 1- 42
Insulated tubes
Drain hose
Clamp
SM830252-01_欧州_Single_8・10HP_TD_SM.indb 96
16/10/14 13:58:13
AMP Air Conditioning
www.ampair.co.uk | [email protected]
