Refrigerant (R32); 6-1.Safety During Installation / Servicing - Toshiba HWT-602S21SM3W-E(TR) Service Manual

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Refrigerant (R32)

This Air to Water Heat Pump adopts the R32 refrigerant which does not damage the ozone layer.
The working pressure of the new refrigerant R32 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 to Water Heat Pump using
the new refrigerant during installation work or servicing time.
The next section describes the precautions for Air to Water Heat Pump 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'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 R32, it is necessary to carry out installation/
servicing safely while taking the following precautions into consideration.
(1) Never use refrigerant other than R32 in an Air to Water Heat Pump which is designed to operate with R32.
If other refrigerant than R32 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.
The refrigerant name R32 is indicated on the visible place of the outdoor unit of the Air to Water Heat Pump
using R32 as refrigerant.
A diameter of the charge port for R32 is the same as that for the R410A's. Be careful not to charge the refrigerant
by mistake.
(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 to Water Heat Pump, 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) When an Air to Water Heat Pump 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 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.
(9) When breaking into the refrigerant circuit to make repairs or for any other purpose conventional procedures
shall be used.
However, for flammable refrigerants it is important that best practice is followed since flammability is a
consideration.
The following procedure shall be adhered to:
• remove refrigerant;
• purge the circuit with inert gas
• evacuate
• purge with inert gas
• open the circuit by cutting or brazing
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