English
6
• Use the following items for the refrigerant piping.
Material
: Jointless phosphor-deoxidized copper pipe.
Size
: See “6-5 Example of connection” to determine the cor-
rect size.
Thickness
: Select a thickness for the refrigerant piping which
complies with national and local laws.
Refrigerant pipe (Gas pipe and Liquid pipe) and refrigerant
branch must meet the condition of design pressure 3.3MPa.
If it is not possible to confirm, use the refrigerant branch kit
selected with 6-5 Example of connection.
Existing pipes must meet the condition of design pressure
3.3MPa.
Specificaly, to confirm that there are no corrosion and the pipe
thickness must not be less than the smallest thickness below.
Temper grade (O type, 1/2H type) in the table indicate the
material types specified in JIS H 3300.
(unit: mm)
* In case of bending 3×D or more (D: O.D. of refrigerant pipe)
(unit: mm)
• For piping work, follow the maximum tolerated length, difference
in height, and length after a branch indicated in the “
6-5 Example
of connection
”.
• A refrigerant branching kit (sold separately) is needed for piping
branches and connection of piping between outdoor unit (in case
of multi system).
Use only separately sold items selected specifically according to
the refrigerant branch kit selection in the “
6-5 Example of con-
nection
”.
• If any tapered pipes are used as branching pipes, replace them.
• If the diameter of existing piping differs from that of outdoor/BS/
indoor units, use a locally-procured irregular socket.
6-2 Protection against contamination
when installing pipes
Protect the piping to prevent moisture, dirt, dust, etc. from
entering the piping.
Note
Exercise special caution to prevent dirt or dust when passing pip-
ing through holes in walls and when passing pipe edges to the
exterior.
6-3 Pipe connection
•
Be sure to perform nitrogen permutation or nitrogen blow
when brazing.
(Refer to figure 11)
Brazing without performing nitrogen permutation or nitrogen
blow into the piping will create large quantities of oxidized film
on the inside of the pipes, adversely affecting valves and com-
pressors in the refrigerating system and preventing normal
operation.
(Refer to figure 11)
1.
Refrigerant pipe
2.
Location to be brazed
3.
Nitrogen
4.
Taping
5.
Handy valve
6.
Regulator
•
The pressure regulator for the nitrogen released when doing
the brazing should be set to 0.02 MPa (about 0.2kg/cm
2
:
Enough to feel a slight breeze on your cheek).
Note
Do not use anti-oxidants when brazing the pipe joints.
Residue can clog pipes and break equipment.
6-4 Connecting the refrigerant piping
1.
Direction to bring out the pipes
The local interunit piping can be connected either forward or to
the sides (taken out through the bottom) as shown in the figure 12.
(When passing out through the bottom, use the knock hole in the
bottom frame.)
(Refer to figure 12)
1.
Left-side connection
2.
Front connection
3.
Right-side connection
Precautions when knocking out knock holes.
• Open knock hole in the base frame by drilling the 4 concave
around it with a 6mm bit.
(Refer to figure 13)
(Refer to figure 13)
1.
Knock hole
2.
Drill
3.
Concave section
• Be sure to avoid damaging the casing.
• After knocking out the holes, we recommend you remove any
burrs and paint them using the repair paint to prevent rusting.
• When passing electrical wiring through the knock holes, protect
the wiring with a conduit or bushings, making sure not to damage
the wiring.
2.
Removing Pinch Piping
CAUTION
Never remove the pinched piping by brazing.
Any gas or oil remaining inside the stop valve may blow off the
pinched piping.
Failure to observe the instructions in procedure below properly may
result in property damage or personal injury, which may be serious
depending on the circumstances.
•
When connecting refrigerant piping to an outdoor unit, remove
the pinch piping.
•
Pinch piping should be removed using the procedure below.
•
Heat Pump series (RQ(C)YQ)
(Refer to figure 14.1)
1.
Pinch piping (2 pipings)
2. Piping is not used
<Procedure>
•
Confirm the shutoff valve is closed.
•
Connect a charge hose to the service port on the liquid side
and suction gas side shutoff valves and remove the gas from
the pinch piping.
•
Cut the pinched piping off with a pipe cutter just above the
marking.
CAUTION
Never remove the pinched piping by brazing.
•
Wait until all oil is dripped out in case the recovery was not
complete, and only then proceed with connection of the field
piping.
•
Heat Recovery series (RQCEQ)
(Refer to figure 14.2)
1.
Pinch piping (3 pipings)
<Procedure>
•
Confirm the shutoff valve is closed.
•
Connect a charge hose to the service port on the liquid side,
suction gas side and HP/LP gas side shutoff valves and
remove the gas from the pinch piping.
•
Cut the pinched piping off with a pipe cutter just above the
marking.
CAUTION
Never remove the pinched piping by brazing.
•
Wait until all oil is dripped out in case the recovery was not
complete, and only then proceed with connection of the field
piping.
Temper grade
O type
outer diameter
φ
6.4
φ
9.5
φ
12.7
φ
15.9
φ
19.1
smallest thickness 0.4*
0.5*
0.7*
0.9*
1.0*
Temper grade
1/2H type
outer diameter
φ
19.1
φ
22.2
φ
25.4
φ
28.6
φ
31.8
φ
34.9
φ
38.1
φ
41.3
smallest thickness
0.6
0.6
0.7
0.8
0.9
1.0
1.1
1.1
Place
Installation period
Protection method
Outdoor
More than a month
Pinch the pipe
Less than a month
Pinch or tape the pipe
Indoor
Regardless of the period
01_EN_3P226891-14T.fm Page 6 Tuesday, September 30, 2014 7:48 PM
