Special Tools For R410A - Fujitsu ASU12R2 Installation Manual

This air conditioner uses new refrigerant HFC (R410A).
The basic installation work procedures are the same as conventional refrigerant (R22) 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 threads per inch.]
(3) Be more careful that foreign matter (oil, water, etc.) does not enter the piping than with
refrigerant(R22) models. Also, when storing the piping ,securely seal the opening 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 side whose composition is
stable.

Special tools for R410A

Tool name
Gauge manifold
Charge hose
Vacuum pump
Gas leakage detector
Copper pipes
It is necessary to use seamless copper pipes and it is desirable
that the amount of residual oil is less than 40 mg/10m. Do not
use copper pipes having a collapsed, deformed or discolored
portion (especially on the interior surface). Otherwise, the ex-
pansion value or capillary tube may become blocked with con-
taminants.
As an air conditioner using R410A incurs pressure higher than
when using R22, it is necessary to choose adequate materials.
Thicknesses of copper pipes used with R410A are as shown in Table1.Never use copper pipes thinner than 0.8mm even
when it is available on the market.
(1) Do not use the existing (for R22) piping and flare nuts.
• If the existing materials are used, the pressure inside the refrigerant cycle will rise and cause breakage, injury,
etc.(Use the special R410A materials.)
(2) When installing and relocating the air conditioner, do not mix gases other than the specified refrigerant(R410A)
to enter the refrigerant cycle.
• If air or other gas enters the refrigerant cycle, the pressure inside the cycle will rise to an abnormally high value
and cause breakage, injury, etc.
When installing pipes shorter than 3m, sound of the outdoor unit will be transferred to the indoor unit, which will
cause large operating sound or some abnormal sound.
Contents of change
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.
To increase pressure resistance, the hose material and base size were changed.
A conventional vacuum pump can be used by installing a vacuum pump adapter.
Special gas leakage detector for HFC refrigerant R410A.
Table 1 Thicknesses of Annealed Copper Pipes
Nominal
diameter
1/4
3/8
WARNING
CAUTION
Thickness (mm)
Outer diameter
R410A
(mm)
6.35 0.80
9.52 0.80
5 cm or over
[ref.] R22
0.80
0.80