44
AY-X10CR
AE-X10CR
AY-X10CR-N
AE-X10CR-N
2.3 Storage of Piping Materials
(1) Types and Storage of Piping Materials
Refrigerant piping materials for air conditioners are broadly classified into the following types.
Refrigerant piping
materials
with heat
insulation
without heat
insulation
(bare copper pipe)
with flare processing
without flare processing
without flare processing
General name
: (a) Piping set
: (b) Copper pipe with insulation
: (c) Bare copper pipe
As R410A features pressure about 1.6 times higher than R22, it is necessary to use a copper pipe which has
a thickness stated in Table 3 and which contains less contaminants. It is necessary to carefully treat/store
copper pipes so that they are not collapesd, deformed or damaged. Due care must also be exercised so that
foreign matters such as dust and water do not enter the pipe interior.
A piping set's open end is sealed with a cap, etc. When storing it, make sure that it is sealed securely. When
storing a cladded copper pipe or bare copper pipe, securely seal the opening with pinching, taping, etc.
(2) Identification
a) Piping set
A copper pipe as piping set for R410A must have a thickness as stated in Table 3, and, as shown in Tables
5 and 6, it also differs from R22 in flare processing and flare nut dimensions. So, it is necessary to choose
a piping set suitable for R410A.
b) Copper Pipe with Insulation
Before using a copper pipe with insulation, make sure that is has a thickness designated for R410A.
c) Bare Copper Pipe
It is necessary to use a bare copper pipe which has a thickness desigtnated in Table 3 and contains less
contaminants. As the bare copper pipe surface is naked, it is necessary to treat it with exceeding care and
adopt a means for identification to prevent improper usage by making it easily discriminable from other
piping materials.
(3) Precautions before Installation
Observe the following precautions when performing the piping connection at the site.
a) Keep any open ends of pipes be sealed with a cap, etc. until connected with the equipment.
b) Exercise great care when performing piping installation on a rainy day.
When water enters into the piping, the lubricating oil may deteriorate and cause the equipment to fail.
c) Carry out the piping connection in as short a time as possible.
If the piping is left open for a long period, fully purge the interior with nitrogen gas or dry it with a vacuum
pump.
3. Installation, Removal and Servicing
3.1 Tools for R410A
In the case of an air conditioner using R410A, in order to prevent any other refrigerant from being
chargedaccidentally, the service port diameter of the outdoor unit control valve (3-way valve) has been changed.
Also, to increase the pressure resisting strength, flare processing dimensions and sizes of opposite sides of flare
nuts (for copper pipes with nominal diameters 1/2 and 5/8) have been changed. During installation/service,
therefore, prepare tools exclusive for R410A shown in (1) below and general tools shown in (2) on page 48.
(1) Tools Exclusive for R410A
a) Gauge Manifold
As R410A is characterized by high pressure, conventional tools cannot be used.
Table 9. Differences between Conventional High/Low Pressure Gauges and Those for R410A
High pressure
gauge (red)
Conventional gauges
Gauges exclusive for R410A
- 0.1 ~ 3.5 MPa
- 76 cmHg ~ 35 kgf/cm
2
- 0.1 ~ 1.7 MPa
- 76 cmHg ~ 17 kgf/cm
2
- 0.1 ~ 5.3 MPa
- 76 cmHg ~ 53 kgf/cm
2
- 0.1 ~ 3.8 MPa
- 76 cmHg ~ 38 kgf/cm
2
Compound
gauge (blue)
In order to prevent any other refrigerant from being charged accidentally, each port of yhe manifold has
been changed in shape.
