En-4
ABOUT THE PRODUCT
21
Precautions for using R410A refrigerant
21 11
WARNING
The basic installation work procedures are the same as conventional refrigerant models.
However, pay careful attention to the following points:
1
Since the working pressure is 1.6 times higher than that of conventional refrigerant (R22) models, some of the
piping and installation and service tools are special. (See the table below.)
Especially, when replacing a conventional refrigerant (R22) model with a new refrigerant R410A model, always
replace the conventional piping and flare nuts with the R410A piping and flare nuts.
2
Models that use refrigerant R410A have a different charging port thread diameter to prevent erroneous charging
with conventional refrigerant (R22) and for safety. Therefore, check beforehand. [The charging port thread
diameter for R410A is 1/2 UNF 20 threads per inch.]
3
Be careful that foreign matter (oil, water, etc.) does not enter the piping than with refrigerant models. Also, when
storing the piping, securely seal the openings by pinching, taping, etc.
4
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 where refrigerant composition is stable.
Special tools for R410A
21 21
Tool name
Contents of change
Gauge manifold
Pressure is high and cannot be measured with a conventional (R22) gauge. To prevent
erroneous mixing of other refrigerants, the diameter of each port has been changed.
It is recommended the gauge with seals –0.1 to 5.3 MPa (30in.Hg to 768 psi) for high
pressure. –0.1 to 3.8 MPa (30in.Hg to 551 psi) for low pressure.
Charge 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.
Gas leakage detector
Special gas leakage detector for HFC refrigerant R410A.
Accessories
21 31
WARNING
For installation purposes, be sure to use the parts supplied by the manufacturer or other prescribed parts. The use
•
of non-prescribed parts can cause serious accidents such as the unit falling, water leakage, electric shock, or fire.
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
Installation
manual
1
(This book)
Binder
3
For binding power supply
cable and connection
cable
Drain cap
7
For outdoor unit drain piping
work
Conduit plate
1
To fix Conduit tube
Drain pipe
1
For outdoor unit drain piping
work
9379069342-02_IM.indb 4
17/5/2556 11:49:26
