Toshiba HWT-601XWHM3W-ETR Service Manual page 15

Refrigerant R32
This Air to Water Heat Pump 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 to Water Heat Pump 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 to Water Heat Pump which is designed
to operate with the specified refrigerant (R32).
If other refrigerant than R32 is used, it may cause personal injury, etc. by a malfunction, a fire, a rupture.
(2) Since R32 is heavier than air, it tends to accumulate at the bottom (near the floor).
Ventilate properly for the working environment to prevent its combustion.
Especially in a basement or a closed room where is the high risk of the accumulation, ventilate the room with
a local exhaust ventilation.
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 or it may cause 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 or it may cause a fire.
(5) No person carrying out work in relation to a refrigerating system which involves exposing any pipe work shall
use any sources of ignition in such a manner that it may lead to the risk of fire or explosion.
All possible ignition sources, including cigarette smoking, should be kept sufficiently far away from the site of
installation, repairing, removing and disposal, during which refrigerant can possibly be released to the
surrounding space.
Prior to work taking place, the area around the equipment is to be surveyed to make sure that there are no
flammable hazards or ignition risks. "No Smoking" signs shall be displayed.
(6) When installing or removing an Air to Water Heat Pump, do not mix air in the refrigerant cycle.
If air or others is mixed with the refrigerant, abnormal high pressure generates in the refrigerating cycle,
causing injury due to the breakage.
(7) After installation work complete, 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 to Water Heat Pump may be dangerous. If a breakdown occurs please
call a qualified Air to Water Heat Pump 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 CO fire extinguisher adjacent to the charging area.
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