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Toshiba 1115551210 (EN)
Appendix
Work instructions:
The existing R22 and R407C piping can be reused for our digital inverter
R410A product installations.
NOTE
Confi rming the existence of scratches or dents on the existing pipes and
confi rming the reliability of the pipe strength are conventionally referred to
the local site.
If the specifi ed conditions can be cleared, it is possible to update
existing R22 and R407C pipes to those for R410A models.
Basic conditions needed to reuse existing pipes
Check and observe the presence of three conditions in the refrigerant piping
works.
1.
Dry
(There is no moisture inside of the pipes.)
2.
Clean
(There is no dust inside of the pipes.)
3.
Tight
(There are no refrigerant leaks.)
Restrictions for use of existing pipes
In the following cases, the existing pipes should not be reused as they
are. Clean the existing pipes or exchange them with new pipes.
1. When a scratch or dent is heavy, be sure to use new pipes for the
refrigerant piping works.
2. When the existing pipe thickness is thinner than the specifi ed “Pipe
diameter and thickness,” be sure to use new pipes for the refrigerant
piping works.
• The operating pressure of R410A is high (1.6 times that of R22 and
R407C). If there is a scratch or dent on the pipe or a thinner pipe is
used, the pressure strength may be inadequate, which may cause the
pipe to break in the worst case.
* Pipe diameter and thickness (mm)
Pipe outer diameter
∅
6.4
∅
9.5
∅
12.7
∅
15.9
∅
19.0
Thickness
R410A
0.8
0.8
0.8
1.0
1.0
R22 (R407C)
• In case the pipe diameter is Ø12.7 mm or less and the thickness is less
than 0.7 mm, be sure to use new pipes for the refrigerant piping works.
3. When the outdoor unit was left with the pipes disconnected, or the gas
leaked from the pipes and the pipes were not repaired and refi lled.
• There is the possibility of rain water or air, including moisture, entering
the pipe.
4. When refrigerant cannot be recovered using a refrigerant recovery unit.
• There is the possibility that a large quantity of dirty oil or moisture
remains inside the pipes.
5. When a commercially available dryer is attached to the existing pipes.
• There is the possibility that copper green rust has been generated.
6. When the existing air conditioner is removed after refrigerant has been
recovered.
Check if the oil is judged to be clearly different from normal oil.
• The refrigerator oil is copper rust green in color.
There is the possibility that moisture has mixed with the oil and rust
has been generated inside the pipe.
• There is discolored oil, a large quantity of residue, or a bad smell.
• A large quantity of shiny metal dust or other wear residue can be seen
in the refrigerant oil.
7. When the air conditioner has a history of the compressor failing and being
replaced.
• When discolored oil, a large quantity of residue, shiny metal dust, or
other wear residue or mixture of foreign matter is observed, trouble will
occur.
8. When temporary installation and removal of the air conditioner are
repeated such as when leased etc.
9. If the type of refrigerator oil of the existing air conditioner is other than
the following oil (Mineral oil), Suniso, Freol-S, MS (Synthetic oil), alkyl
benzene (HAB, Barrel-freeze), ester series, PVE only of ether series.
• The winding-insulation of the compressor may deteriorate.
NOTE
The above descriptions are results have been confi rmed by our company
and represent our views on our air conditioners, but do not guarantee the
use of the existing pipes of air conditioners that have adopted R410A in
other companies.
Branching pipe for simultaneous operation system
• In the concurrent twin system, when TOSHIBA has specifi ed that
branching pipe is to be used, it can be reused.
Branching pipe model name:
RBC-TWP30E2
On the existing air conditioner for simultaneous operation system (twin
system), there are cases of branch pipes being used that have insuffi cient
compressive strength. In such case, please change the piping to a branch
pipe for R410A.
Curing of pipes
When removing and opening the indoor or outdoor unit for a long time, cure
the pipes as follows:
• Otherwise rust may be generated when moisture or foreign matter due to
condensation enters the pipes.
• The rust cannot be removed by cleaning, and new pipes are necessary.
Placement location
Term
Curing manner
Outdoors
1 month or more
Pinching
Less than 1 month
Pinching or taping
Indoors
Every time
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