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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
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Tool name
Contents of change
Gauge manifold
Pressure is high and cannot be measured with a
conventional 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
(-1 to 53 bar) for high pressure. –0.1 to 3.8 MPa (-1 to 38
bar) 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 21
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
Installation
manual
1
(This book)
Drain cap
2
For outdoor unit drain piping work
Drain pipe
1
For outdoor unit drain piping work
Binder
3
For binding power supply cable and
connection cable
One-touch bush
2
For power supply cable and
connection cable installation
Optional parts
21 41
CAUTION
The following parts are optional parts specific to R410A refrigerant.
Do not use parts other than those listed below.
Refer to the installation manual for the Branch box and the Separation tubes.
Parts name
Model name
Separation tube
UTP-SX248A
Branch box
3 Branches
UTP-PY03A
2 Branches
UTP-PY02A
External connect kit
(for External input/output)
UTY-XWZXZ3
External connect kit
(for Base heater)
UTY-XWZXZ4
Operating range
21 21
Operating range
Temperature
Indoor air intake
Outdoor air intake
Cooling
Maximum
32 °C DB
46 °C DB
Minimum
18 °C DB
-5 °C DB
Heating
Maximum
30 °C DB
24 °C DB
Minimum
16 °C DB
-15 °C DB
Indoor humidity about 80% or less
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