Refrigerant r410a – Toshiba CARRIER RAV-SP300AT2-UL User Manual

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This air conditioner adopts the new refrigerant HFC

(R410A) which does not damage the ozone layer.
The working pressure of the new refrigerant 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

refrigerating 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 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

materials exclusive for R410A, it is necessary to

carry out installation/servicing safely while taking

the following precautions into consideration.
1. Never use refrigerant other than R410A in an air

conditioner which is designed to operate with

If other refrigerant than 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

The refrigerant name R410A is indicated on the

visible place of the outdoor unit of the air

conditioner using 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

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. When an air conditioning system charged with a

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.

7. Be sure to carry out installation or removal

according to the installation manual.
Improper installation may cause refrigeration

trouble, water leakage, electric shock, fire, etc.

8. Unauthorized modifications to the air conditioner

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.

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

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 0.0001 lbs / 32’ 10” (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 R410A incurs pres-

sure higher than when using R22, it is necessary

to choose adequate materials.
Thicknesses of copper pipes used with R410A

are as shown in Table 6-2-1. Never use copper

pipes thinner than 0.03” (0.8 mm) even when it is

available on the market.