English
11
CAUTION
〈
Precautions when laying power supply wiring
〉
Use round pressure terminals for connections to the power supply
terminal block.
When none is available, follow the instructions below.
•
Do not connect wiring of different thicknesses to the power supply
terminal block. (Slack in the power supply 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 supply 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.
〈
Precautions 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.)
8-5 In case of a local setting
If necessary, do the local settings as mentioned in the table below. For
setting, refer to the plate “Cares to be taken in servicing” attached to the
cover of control box.
Typical local settings
∗
For other settings than mentioned in the table below, refer to the
equipment design materials and service manual.
CAUTION
A separate adapter (sold separately as an accessory) for external
control of an outside unit is necessary when doing a demand oper-
ation from an external instruction, setting of cooling and heating
through a centralized remote controller for cooling and heating
(sold separately as an accessory) and setting of centralized inter-
lock. For details, refer to the manual attached to the adapter.
9.
REFRIGERANT PIPING
CAUTION
After completing installation, be sure to open the valves.
(See
9-9 Additional refrigerant charge
for details) (Operating the
unit with the valves shut will break the compressor.)
Use R410A to add refrigerant. (The R410A refrigerant cylinder has
a pink stripe painted around it.)
All field piping must be installed by a licensed refrigeration techni-
cian and must comply with relevant local and national regulations.
CAUTION TO BE TAKEN WHEN BRAZING REFRIGERANT PIPING
Do not use flux when brazing copper-to copper refrigerant piping.
(Particularly for the HFC refrigerant piping) Therefore, use the
phosphor copper brazing filler metal (B-Cu93P-710/795: ISO
3677) which does not require flux.
Note: Flux has an extremely negative effect on refrigerant piping
systems. For instance, if the chlorine based flux is used, it
will cause pipe corrosion or, in particular, if the flux contains
fluorine, it will damage the refrigerant oil.
NOTE
•
Installation tools:
Gauge manifold, charge hose, etc.
Make sure to use installation tools that are exclusively used for
R410A installations to withstand the pressure and to prevent for-
eign materials (e.g. mineral oils such as SUNISO and moisture)
from mixing into the system.
(The screw specifications differ for R410A and R407C.)
Vacuum pump
1.
Use a 2-stage vacuum pump with a non-return valve.
2.
Make sure the pump oil does not flow oppositely into the system
while the pump is not working.
3.
Use a vacuum pump which can evacuate to 500 microns.
9-1 Selection of piping material
1.
Foreign materials inside pipes (including oils for fabrication) must be
9 mg/10 ft or less.
2.
Use the following material specification for refrigerant piping:
•
Construction material: Phosphoric acid deoxidized seamless
copper for refrigerant.
•
Size: Determine the proper size referring to chapter “Example of
connection”.
•
The wall thickness of the refrigerant piping should comply with
relevant local and national regulations. For R410A the design
pressure is 450 psig (3.1 MPa).
3.
Make sure to use the particular branches of piping that have been
selected referring to chapter “Example of connection”.
4.
Refer to chapter “Stop valve operation procedure” in 9-10 about the
stop valve operation procedure.
5.
Make sure to perform the piping installation within the range of the
maximum allowable pipe length, allowable level difference and allow-
able length after branching as indicated in chapter “Example of con-
nection”
6.
For installation of the refrigerant branch kit, refer to the installation
manual delivered with the kit.
And follow the conditions listed below.
•
Mount the REFNET joint so that it branches either horizontally or
vertically.
•
Mount the REFNET header so that it branches horizontally.
(Refer to figure 22)
1.
Horizontal connections
2.
Up to ± 30° or vertically
3.
Horizontal connections
7.
To connect the piping between outside units, an optional piping kit
(multi connection piping kit) is always required. When installing the
piping, follow the instructions in the installation manual that comes
with the kit.
Restriction for the installation of the outside unit multi connection
piping kit
• Install the joint horizontally within a lean of ±15° with caution name-
plate on top. Refer to figure 23 (Fig. A).
Do not connect it vertically. Refer to figure 23 (Fig. B).
• Reserve the straight part of 19-11/16 in. (500 mm) or more to the
branch pipe and do not bend the local pipe in that area. Straight part
of 19-11/16 in. (500 mm) or more can be reserved if a local pipe
Tightening torque
(ft.·lbf. (N·m))
M5 (Power supply terminal block)
2.21-3.02
(3.0-4.1)
M5 (Ground)
M3 (Transmission wiring terminal block)
0.59-0.72
(0.80-0.96)
(1) Setting of switching between
cooling and heating
This setting is done when switching between cooling and
heating is performed by a switching remote controller (sold
separately as an accessory) installed on the outside unit.
(2) Setting to prohibit sequenced
start
This setting is done when the outside units are not started in
a sequenced order.
(3) Setting of centralized interlock
Setting of external demand
These settings are done when the interlocks are connected
in a lump-sum manner or when performing a demand opera-
tion by external instruction.
(4) Setting of abnormal display
when interlock contact is OFF
This setting is done when making an abnormal display (HJ)
on a remote controller when the interlock contact is OFF
(when the heat source water pump is not operated).
Power supply wire
Round pressure
terminal
Connect same-
thickness wiring
to both sides.
It is forbidden to
connect two to
one side.
It is forbidden to
connect wiring of
different thicknesses.
Round pressure terminal
Cup washer
Cut out section
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Summary of Contents for RWEYQ72PCYD
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