Toshiba RAS-18J2AVRG-E, Installation Manual

17

A

P

P

E

N

D

IX

APPENDIX

W

ork instructions

The existing R22 and R410A

 piping can be reused for 

inverter R32 product installations.

W

ARNING

Con

fi

rming the existence of scratches or dents on

the existing pipes and con

fi

rming the reliability of

the pipe strength are conventionally referred to the

local site.

If the speci

fi

ed 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.)

2. 

Clean

 (There is no dust inside of the pipes.)

3. 

T

ight

 (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 

speci

fi

ed “Pipe diameter and thickness,” be sure to 

use new pipes for the refrigerant piping works.

y

The operating pressure of R32 or R410A

 is high 

(1.6 times that of R22). 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

Ø6.4

Ø9.5

Ø12.7

Thickness

R32, R410A

0.8

0.8

0.8

R22

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 re

fi

lled.

y

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.

y

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.

y

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 dif

ferent from 

normal oil.

y

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.

y

There is discolored oil, a large quantity of residue, 

or a bad smell.

y

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.

y

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.

y

The winding-insulation of the compressor may 

deteriorate.

NOTE

The above descriptions are results have been con

fi

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 R32 or R410A 

in other companies.

Curing of pipes

When removing and opening the indoor or outdoor unit for

a long time, cure the pipes as follows:

y

Otherwise rust may be generated when moisture or 

foreign matter due to condensation enters the pipes.

y

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

Are there scratches or dents on the existing pipes?

Is it possible to operate the existing air conditioner?

y

After the existing air conditioner is operated in cooling 

mode for approx. 30 minutes or longer

,* recover the 

refrigerant.

y

For cleaning the pipes and recovering oil

y

Refrigerant recovery: Pump down method

y

Remove the existing air conditioner from the piping 

and carry out 

fl

ushing (nitrogen pressure 0.5 MPa) to 

remove any remains inside of the pipe.

Note:

In case of twin pipes, also be sure to 

fl

ush the 

branching pipe.

Connect the indoor / outdoor units to the existing pipe.

y

Use a 

fl

are nut attached to the main unit for the indoor 

/ outdoor units. (Do not use the 

fl

are nut of the existing 

pipe.)

y

Re-machine the 

fl

are machining size to size for R32 

or R410A.

y

(Airtight test), V

acuum dry

, Refrigerant charge, Gas 

leak check

Test run

W

as 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.

y

Use new pipes.

Clean the pipes or use new pipes.

Piping necessary to change the 

fl

are nut / machining 

size due to pipe compression

1) Flare nut width: H

H

(mm)

Copper pipe outer 

diameter

Ø6.4

Ø9.5

Ø12.7

For R32, R410A

17

22

26

For R22

Same as above

24

2) Flare machining size: 

A

A

(mm)

Copper pipe outer 

diameter

Ø6.4

Ø9.5

Ø12.7

For R32, R410A

9.1

13.2

16.6

For R22

9.0

13.0

16.2

Becomes a little larger for R32 or R410A

Do not apply refrigerator oil to the 

fl

are surface.

(If there is discharge of remains, it is judged that a 

large quantity of remains are present.)

YES

YES

NO

NO

NO

YES

Nitrogen gas pressure 0.5 MPa