Carrier 0131CP Installation Manual Download

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Are there scratches or dents on the existing pipes?

Is it possible to operate the existing air conditioner?

After the existing air conditioner is operated in cooling
mode for approx. 30 minutes or longer,* recover the
refrigerant.
For cleaning the pipes and recovering oil

Refrigerant recovery: Pump down method

Remove the existing air conditioner from the piping
and carry out flushing (nitrogen pressure 0.5 MPa) to
remove any remains inside of the pipe.

Note:

In case of twin pipes, also be sure to flush the

branching pipe.

Connect the indoor / outdoor units to the existing pipe.

Use a flare nut attached to the main unit for the indoor
/ outdoor units. (Do not use the flare nut of the existing
pipe.)

Re-machine the flare machining size to size for R32.

(Airtight test), Vacuum dry, Refrigerant charge, Gas
leak check

Test run

Was largely discolored oil or a large quantity

of remains discharged? (When the oil deteriorates,

the color of the oil changes to a muddy

or black color.)

Existing pipes: Cannot be used.

Use new pipes.

Clean the pipes or use new pipes.

(If there is discharge of remains, it is judged that a
large quantity of remains are present.)

YES

Nitrogen gas pressure 0.5 MPa

Piping necessary to change the flare nut / machining

size due to pipe compression

1) Flare nut width: H

(mm)

Copper pipe
outer diameter

Ø6.4

Ø9.5 Ø12.7 Ø15.9

For R32, R410A

For R22

Same as above

Copper pipe
outer diameter

Ø6.4 Ø9.5 Ø12.7 Ø15.9

For R32, R410A

9.1

13.2

16.6

19.7

For R22

9.0

13.0

16.2

19.4

2) Flare machining size: A

(mm)

Becomes a little larger for R32

Do not apply refrigerator oil to the flare surface.

Ø19.1

Ø1 .

9 1

Work instructions

The existing R22 and R410A piping can be reused for
inverter R32 product installations.

WARNING

Confirming the existence of scratches or dents on
the existing pipes and confirming the reliability of
the pipe strength are conventionally referred to the
local site.
If the specified conditions can be cleared, it is
possible to update existing R22 and R410A pipes
to those for R32 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.)

Clean

(There is no dust inside of the pipes.)

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

specified “Pipe diameter and thickness,” be sure to
use new pipes for the refrigerant piping works.

The operating pressure of refrigerant is high.

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)

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 refilled.

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 confirmed
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 R32 in other
companies

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

Appendix