Refrigerant R32 Or R410A; Safety During Installation/Servicing; Refrigerant Piping Installation - Toshiba RAV-RM301KRTP Series Service Manual

This air conditioner adopts the new refrigerant HFC
(R410A) which does not damage the ozone layer.
The working pressure of the new refrigerant R32 or
R410A is 1.6 times higher than conventional
refrigerant (R22). The refrigerating oil is also
changed in accordance with change of refrigerant,
so be careful that water, dust, and existing
refrigerant or refriger-ating oil are not entered in the
refrigerant cycle of the air conditioner using the new
refrigerant during installation work or servicing time.
The next section describes the precautions for air
conditioner using the new refrigerant.
Conforming to contents of the next section together
with the general cautions included in this manual,
perform the correct and safe work.

6-1. Safety During Installation/Servicing

As R32 or R410A's pressure is about 1.6 times
higher than that of R22, improper installation/
servicing may cause a serious trouble. By using
tools and materi-als exclusive for R32 or R410A, it is
necessary to carry out installation/servicing safely
while taking the follow-ing precautions into
consideration.
1. Never use refrigerant other than R32 or R410A
in an air conditioner which is designed to operate
with R32 or R410A. If other refrigerant than R32
or R410A is mixed, pressure in the refrigeration
cycle becomes abnormally high, and it may
cause personal injury, etc. by a rupture.
2. Confirm the used refrigerant name, and use tools
and materials exclusive for the refrigerant R32 or
R410A. The refrigerant name R32 or R410A is
indicated on the visible place of the outdoor unit
of the air conditioner using R32 or R410A as
refrigerant.
To prevent mischarging, the diameter of the
service port differs from that of R22.
3. If a refrigeration gas leakage occurs during
installation/servicing, be sure to ventilate fully. If
the refrigerant gas comes into contact with fire, a
poisonous gas may occur.
4. When installing or removing an air conditioner,
do not allow air or moisture to remain in the
refrigeration cycle.
Otherwise, pressure in the refrigeration cycle
may become abnormally high so that a rupture or
personal injury may be caused.
5. After completion of installation work, check to
make sure that there is no refrigeration gas
leakage. If the refrigerant gas leaks into the
room, coming into contact with fire in the fan-
driven heater, space heater, etc., a poisonous
gas may occur.

6. REFRIGERANT R32 or R410A

6. When an air conditioning system charged with a
7. Be sure to carry out installation or removal
8. Unauthorized modifications to the air conditioner

6-2. Refrigerant Piping Installation

6-2-1. Piping Materials and Joints Used
For the refrigerant piping installation, copper pipes
and joints are mainly used. Copper pipes and joints
suitable for the refrigerant must be chosen and
installed. Furthermore, it is necessary to use clean
copper pipes and joints whose interior surfaces are
less affected by contaminants.
1. Copper Pipes
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large volume of refrigerant is installed in a small
room, it is necessary to exercise care so that,
even when refrigerant leaks, its concentration
does not exceed the marginal level.
If the refrigerant gas leakage occurs and its
concentration exceeds the marginal level, an
oxygen starvation accident may result.
according to the installation manual.
Improper installation may cause refrigeration
trouble, water leakage, electric shock, fire, etc.
may be dangerous.
If a breakdown occurs please call a qualified air
conditioner technician or electrician.
Improper repair may result in water leakage,
electric shock and fire, etc.
It is necessary to use seamless copper pipes
which are made of either copper or copper alloy
and it is desirable that the amount of residual oil
is less than 40 mg/10 m.
Do not use copper pipes having a collapsed,
deformed or discolored portion (especially on the
interior surface).
Otherwise, the expansion valve or capillary tube
may become blocked with contaminants.
As an air conditioner using R32 or R410A incurs
pres-sure higher than when using R22, it is
necessary to choose adequate materials.
Thicknesses of copper pipes used with R32 or
R410A are as shown in Table 6-2-1.
Never use copper pipes thinner than 0.8 mm
even when it is available on the market.
FILE NO. SVM-18059