Toshiba RAV-SM2804AT7ZG Basic Conditions Needed to Reuse the Existing Pipe, Curing of Pipes

6-6. Instructions for Re-use Piping of R22 or R407C

Instruction of Works:

The existing R22 and R407C piping can be reused for our digital inverter R410A products 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 definite conditions can be cleared,

it is possible to update the existing R22 and R407C pipes to those for R410A models.

6-6-1. Basic Conditions Needed to Reuse the Existing Pipe

Check and observe three conditions of 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 is no refrigerant leak.)

6-6-2. Restricted Items to Use the Existing Pipes

In the following cases, the existing pipes cannot 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 the new pipes for the works.

2.When the thickness of the existing pipe is thinner than the specified “Pipe diameter and thickness” be sure to use the new pipes for the works.

•The operating pressure of R410A is high

(1.6 times of R22 and R407C). If there is a scratch or dent on the pipe or thinner pipe is used, the pressure strength is poor and may cause break- age of the pipe at the worst.

5.A dryer on the market is attached to the existing pipes.

•There is possibility that copper green rust generated.

6.Check the oil when the existing air conditioner was removed after refrigerant had been recovered.

In this case, if the oil is judged as clearly different compared with normal oil

•The refrigerator oil is copper rust green :

There is possibility that moisture is mixed with the oil and rust generates inside of the pipe.

•There is discolored oil, a large quantity of the remains, or bad smell.

•A large quantity of sparkle remained wear-out powder is observed in the refrigerator oil.

7.The air conditioner which compressor was ex- changed due to a faulty compressor.

When the discolored oil, a large quantity of the remains, mixture of foreign matter, or a large quantity of sparkle remained wear-out powder is observed, the cause of trouble will occur.

8.Installation and removal of the air conditioner are repeated with temporary installation by lease and etc.

9.In case that type of the 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.

•Winding-insulation of the compressor may become inferior.

NOTE

The above descriptions are results of confirmation by our company and they are views on our air conditioners, but they do not guarantee the use of the existing pipes of the air conditioner that adopted R410A in other companies.

∗Pipe diameter and thickness (mm)

Reference outside	Wall thickness	Material
diameter (mm)	(mm)
6.4	0.8	—
9.5	0.8	—
12.7	0.8	—
15.9	1.0	—
19.1	1.2	—
22.2	1.0	Half hard
28.6	1.0	Half hard

•In case that the pipe diameter is Ø12.7 mm or less and the thickness is less than 0.7 mm, be sure to use the new pipes for works.

3.The pipes are left as coming out or gas leaks. (Poor refrigerant)

•There is possibility that rain water or air including moisture enters in the pipe.

4.Refrigerant recovery is impossible.

(Refrigerant recovery by the pump-down operation on the existing air conditioner)

•There is possibility that a large quantity of poor oil or moisture remains inside of the pipe.

6-6-3. Branching Pipe for Simultaneous Operation System

•In the concurrent twin system, when TOSHIBA- specified branching pipe is used, it can be reused. Branching pipe model name:

RBC-TWP30E-2, RBC-TWP50E-2, RBC-TRP100E On the existing air conditioner for simultaneous operation system (twin system), there is a case of using branch pipe that has insufficient compressive strength. In this case please change it to the branch pipe for R410A.

6-6-4. Curing of Pipes

When removing and opening the indoor unit or outdoor unit for a long time, cure the pipes as follows:

•Otherwise rust may generate when moisture or foreign matter due to dewing enters in the pipes.

•The rust cannot be removed by cleaning, and a new piping work is necessary.

Place position	Term	Curing manner
Outdoors	1 month or more	Pinching
	Less than 1 month	Pinching or taping
Indoors	Every time

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