En-4
ABOUT THE PRODUCT
2.
Caution when using R410A refrigerant
2. 1.
Pay careful attention to the following points :
Since the working pressure is 1.6 times higher than that of R22 models, some of the piping and installation and
•
service tools are special. (See the table in the SPECIAL TOOLS FOR R410A section.)
Especially, when replacing a conventional refrigerant (other than R410A) model with a new refrigerant R410A
model, always replace the conventional piping and
fl
are nuts with the R410A piping and
fl
are nuts.
Models that use refrigerant R410A have a different charging port thread diameter to prevent erroneous charging
•
with R22, R407C and for safety. Therefore, check beforehand. [The charging port thread diameter for R410A is
1/2 UNF 20 threads per inch.]
Be more careful than the installation of the refrigerant (other than R410A) models, not to enter foreign matters
•
(oil, water, etc.) and other refrigerant into the piping. Also, when storing the piping, securely seal the openings by
pinching, taping, etc.
When charging the refrigerant, take into account the slight change in the composition of the gas and liquid
•
phases, and always charge from the liquid phase side whose composition is stable.
Special tools for R410A
2. 2.
Tool name
Contents of change for R22 tool
Gauge manifold
Pressure is huge and cannot be measured with a conventional gauge. To prevent er-
roneous mixing of other refrigerants, the diameter of each port has been changed.
It is recommended to use a gauge manifold with a high pressure display range -0.1 to 5.3
MPa and a low pressure display range -0.1 to 3.8 MPa.
Charging hose
To increase pressure resistance, the hose material and base size were changed.
Vacuum pump
A conventional vacuum pump can be used by installing a vacuum pump adapter.
A conventional vacuum pump can be used by installing a vacuum pump adapter.
•
Be sure that the pump oil does not back
fl
ow into the system. Use one capable for
•
vacuum suction of -100.7kPa (5 Ton, -755mmHg).
Gas leakage detector
Special gas leakage detector for HFC refrigerant R410A.
Accessories
2. 3.
Use connecting parts as required.
Do not throw away the connecting parts until the installation has been complete.
Name and shape
Q’ty
Application
Name and shape
Q’ty
Application
Speci
fi
cations
manual
1
—
Joint pipe B
1
For connecting gas pipe
(L type)
Installation
manual
1
(This book)
Binder
9
For binding power cable
and transmission cable
Joint pipe A
1
For connecting gas pipe
(Straight type)
Combinations
2. 4.
A maximum of 3 outdoor units can be connected to 1 refrigerant system.
The combination of outdoor units per refrigerant system and the number of indoor units that can be connected are as
follows:
9378945029-03_IM_EN.indb 4
9378945029-03_IM_EN.indb 4
2011-9-20 16:25:45
2011-9-20 16:25:45
