6
English
〈
For refrigerant piping of outdoor units, see the installation
manual attached to the outdoor unit.
〉
〈
Execute heat insulation work completely on both sides of
the gas piping and the liquid piping. Otherwise, a water
leakage can result sometimes.
〉
(When using a heat pump, the temperature of the gas piping
can reach up to approximately 120
°
C,
so
use
insulation which
is sufficiently resistant
.)
〈
Also, in cases where the temperature and humidity of the
refrigerant piping sections might exceed 30°C or RH80%,
reinforce the refrigerant insulation. (20 mm or thicker) Con-
densation may form on the surface of the insulating mate-
rial.
〉
〈
Before refrigerant piping work, check which type of refrig-
erant is used. Proper operation is not possible if the types
of refrigerant are not the same.
〉
CAUTION
•
Use a pipe cutter for the type of refrigerant.
•
To prevent dust, moisture or other foreign matter from
infiltrating the tube, either pinch the end or cover it with
tape.
•
Do not allow anything other than the designated refrig-
erant to get mixed into the refrigerant circuit, such as air,
etc. If any refrigerant gas leaks while working on the
unit, ventilate the room thoroughly right away.
• The outdoor unit is charged with refrigerant.
• Check the pipe connector for gas leaks, then insulate it as
shown in the drawing below.
• Wrap only the gas line side of the insulation for fitting (union)
with the sealing pad.
•
Ventilate if refrigerant gas leaks while performing work.
• Connection of piping
It takes care of one’s health with the wet cloth so that part
A should not exceed 80°C when the row is put.
• Make absolutely sure to execute heat insulation works on the
pipe-connecting section after checking gas leakage by thor-
oughly studying the following figure and using the attached
heat insulating materials for fitting. (Fasten both ends with
the clamps (accessory).)
(Refer to Fig. 1)
• Wrap the sealing pad (accessory) only around the insulation
for the joints on the gas piping side.
CAUTION
Be sure to insulate any field piping all the way to the piping
connection inside the unit. Any exposed piping may cause
condensation or burns if touched.
CAUTION
CAUTION TO BE TAKEN WHEN BRAZING REFRIGER-
ANT PIPING
Do not use flux when brazing refrigerant piping. Therefore,
use the phosphor copper brazing filter metal (BCuP) which
does not require flux.
(Flux has extremely harmful infulence on refrigerant piping
sysems. For instance, if the chlorine based flux is used, it will
cause pipe corrosion or, in particular, if the flux contains flu-
orine, it will damage the refrigerant oil.)
• Before brazing local refrigerant piping, nitrogen gas shall be
blown through the piping to expel air from the piping.
If your brazing is done without nitrogen gas blowing, a large
amount of oxide film develops inside the piping, and could
cause system malfunction.
• When brazing the refrigerant piping, only begin brazing after
having carried out nitrogen substitution or while inserting
nitrogen into the refrigerant piping. Once this is done, con-
nect the indoor unit with a flared or a flanged connection.
• Nitrogen should be set to 0.02 MPa (0.2 kg/cm
2
) with a pressure-
reducing valve if brazing while inserting nitrogen into the piping.
7.
DRAIN PIPING WORK
〈〈
Rig the drain pipe as shown below and take measures
against condensation. Improperly rigged piping could lead
to leaks and eventually wet furniture and belongings.
〉〉
(1)
Carry out the drain piping
• The diameter of the drain pipe should be greater than or
equal to the diameter of the connecting pipe (vinyl tube;
pipe size: 25 mm; outer dimension: 32 mm).
• Keep the drain pipe short and sloping downwards at a gra-
dient of at least 1/100 to prevent air pockets from forming.
• If the drain hose cannot be sufficiently set on a slope,
execute the drain raising piping.
• To keep the drain hose from sagging, space hanging
wires every 1 to 1.5 m.
Field supply piping
Brazing
Part A
Indoor unit
Mid sealing pad
(accessory)
Gas pipe
Clamp
(× 4 accessory)
Insulation for fitting
(accessory)
(For gas pipe)
Fig. 1
Liquid pipe
Insulation for fitting
(accessory)
(For liquid pipe)
Refrigerant
piping
Part to be
brazed
Taping
Pressure-
reducing
valve
hands valve
Nitrogen
Nitrogen
01_EN_3P233622-5F.fm Page 6 Thursday, December 18, 2008 4:21 PM
