Toshiba MCY-MUG0401HSW-E Service Manual page 15

About refrigerant R32
This air conditioner adopts a new HFC type refrigerant (R32) which does not deplete the ozone layer.
1. Safety Caution Concerned to Refrigerant R32
Be sure that water, dust, the former refrigerant or the former refrigerating oil is not mixed into the refrigerating
cycle of the air conditioner with refrigerant R32 during installation work or service work. If an incorrect work or
incorrect service is performed, there is a possibility to cause a serious accident. Use the tools and materials
exclusive to R32 to purpose a safe work.
2. Safety and Cautions on Installation/Service
<Safety items>
When gas concentration and ignition energy are happened at the same time, R32 has a slight possibility of
burning. Although it will not ignite under normal work environment conditions, be aware that the flame spreads
if ignition should occur.
It is necessary to carry out installation/servicing safely while taking the following precautions into consideration.
1 Never use refrigerant other than specified refrigerant (R32) in an air conditioner which is designed to operate
with the specified refrigerant (R32).
If other refrigerant than R32 is used, it may cause personal injury, etc. due to a malfunction, a fire, or rupture.
2 Since R32 is heavier than air, it tends to accumulate on the bottom (near the floor).
Ventilate properly for the working environment to prevent its combustion.
Especially in a basement or a closed room where there is a high risk of the accumulation, ventilate the room
with a local exhaust ventilator.
If refrigerant leakage is confirmed in the room or the place where the ventilation is insufficient, do not work
until the proper ventilation is performed and the work environment is improved.
3 When performing brazing work, be sure to check for leakage refrigerant or residual refrigerant. If the leakage
refrigerant comes into contact with fire, a poisonous gas may occur, causing a fire. Keep adequate ventilation
during the work.
4 When refrigerant gas leaks during work, execute ventilation. If the leakage refrigerant comes into contact with
a fire, a poisonous gas may occur, causing a fire.
5 In places where installing / repairing air-conditioning equipment, etc., keep the source of ignition such as gas
combustion equipment, petroleum combustion equipment, electric heater etc. away. Do not smoke in the
place.
6 When installing or removing an air conditioner, do not mix air in the refrigerant cycle.
If air or others is mixed with the refrigerant, abnormal high pressure occurs in the refrigerating cycle, causing
injury due to the breakage.
7 After installation work has been completed, confirm that refrigerant gas is not leaking on the flare connection
part or others. If leaked refrigerant comes to contact with a fire, toxic gas may occur, causing a fire.
8 Perform the installation work and re-installation according to the installation manual.
Pay attention especially to the area of application. Improper installation may cause refrigeration trouble,
water leakage, electric shock, or fire etc.
9 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.
10 Carry out the airtight test with nitrogen at a specified pressure. Do not use oxygen or acetylene gas
absolutely as it may cause an explosion.
11 Always carry a refrigerant leakage detection sensor during the work and work while checking that no
refrigerant leaks around working environment.
12 If the leakage refrigerant comes into contact with fire, it may cause a fire.
Have a dry powder or CO2 fire extinguisher adjacent to the charging area.
<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 be mixed, be sure to
recharge the refrigerant.
3 Do not mix the other refrigerant or refrigerating oil with the refrigerant.
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