Pipe Materials; Copper Pipe; Joint; Caution Items - Toshiba RAV-GM301ATP-E Service Manual

<Caution items>
1) The opposite side dimension of the air-conditioner's flared nut using R32 and the
shape of the charge port are the same as those of R410A.
2) Be careful not to charge refrigerant by mistake. Should the different type of refrigerant mix in,
be sure to recharge the refrigerant
3) Do not mix the other refrigerant or refrigerating oil with the refrigerant.
4) Since the pressure of R32 is high 1.6 times of that of the former refrigerant (R22),
use tools and parts with high pressure withstand specification similar to R410A.
5) In the installation time, use clean pipe materials and work with great attention so that
water and others do not mix in because pipes are affected by impurities such as water,
oxide film, oil, etc. Use the clean pipes. Be sure to braze while flowing nitrogen gas
in the pipe. (Never use gas other than nitrogen gas.)
6) For the earth protection, use a vacuum pump for air purge.
7) R32 refrigerant is Single-component refrigerant that does not change its composition.
Although it is possible to charge the refrigerant with either liquid or gas, charge it with liquid.
(If using gas for charging, composition of the refrigerant changes and then
characteristics of the air conditioner change.)

3. Pipe Materials

For the refrigerant pipes, copper pipe and joints are mainly used.
It is necessary to select the most appropriate pipes to conform to the standard.
Use clean material in which impurities adhere inside of pipe or joint to a minimum.

1) Copper pipe

<Piping>
The pipe thickness, flare finishing size, flare nut and others differ according to a refrigerant type.
When using a long copper pipe for R32, it is recommended to select "Copper or copper-base pipe
without seam" and one with bonded oil amount 40mg/10m or less.
Also do not use crushed, deformed, discolored (especially inside) pipes.
(Impurities cause clogging of expansion valves and capillary tubes.)
<Flare nut>
Use the flare nuts which are attached to the air conditioner unit.
Be sure to select the pipes with copper thickness in the table below since the pressure of an
air conditioner using R32 is higher than that of R22.
Nominal
diameter
1/2
3/8
1/2
5/8

2) Joint

The flare joint and socket joint are used for joints of the copper pipe.
The joints are rarely used for installation of the air conditioner.
However clear impurities when using them.
Outer Thickness (mm)
diameter (mm) R410A or R32
6.4 0.80
9.5 0.80
12.7 0.80
15.9 1.00
– 15 –
Make sure not to use a thin copper
pipe such as 0.7 mm copper
thichness in the market.
FILE NO. SVM-18042