• Outdoor Units • HEAT PUMP • RWEYQ-MY1
1
10
• VRV Systems • Outdoor Units
100
10
Installation of outdoor units
10 - 9 Refrigerant piping
C
AUTION
After completing installation, be sure to open the valve.
(See
10-9-9 Additional refrigerant charge for details
) (Operating the unit with the valve shut will break the compressor.)
Use R410A to add refrigerant. (The R410A refrigerant cylinder has a pink stripe painted around it.)
All field piping must be installed by a licensed refrigeration technician and must comply with relevant local and national regulations.
CAUTION TO BE TAKEN WHEN BRAZING REFRIGERANT PIPING
Do not use flux when brazing copper-to copper refrigerant piping.
(Particularly for the HFC refrigerant piping) Therefore, use the phosphor copper brazing filler metal (BCuP-2: JIS Z 3264/B-Cu93P-710/ 795: ISO
3677) which does not require flux.
(Flux has extremely harmful influence on refrigerant piping systems. For instance, if the chlorine based flux is used, it will cause pipe corrosion or,
in particular, if the flux contains fluorine, it will damage the refrigerant oil.)
N
OTE
Installation tools:
Gauge manifold, charge hose, etc.
Make sure to use installation tools that are exclusively used for R410A installations to withstand the pressure and to prevent foreign materials (e.g.
mineral oils such as SUNISO and moisture) from mixing into the system.
(The screw specifications differ for R410A and R407C.)
Vacuum pump
1Use a 2-stage vacuum pump with a non-return valve.
2Make sure the pump oil does not flow oppositely into the system while the pump is not working.
3Use a vacuum pump which can evacuate to –100.7 kPa (5Torr, –755mmHg).
10 - 9 - 1
Selection of piping material
1
Foreign materials inside pipes (including oils for fabrication) must be 30mg/10m or less.
2
Use the following material specification for refrigerant piping:
•
Construction material: Phosphoric acid deoxidized seamless copper for refrigerant.
•
Size: Determine the proper size referring to chapter “Example of connection”.
•
The wall thickness of the refrigerant piping should comply with relevant local and national regulations. For R410A the design pressure is 4.0
MPa.
3
Make sure to use the particular branches of piping that have been selected referring to chapter “Example of connection”.
4
Refer to chapter “Shutoff valve operation procedure” in 9-10 about the shutoff valve operation procedure.
5
Make sure to perform the piping installation within the range of the maximum allowable pipe length, allowable level difference and allowable length
after branching as indicated in chapter “Example of connection”
6
For installation of the refrigerant branching kit, refer to the installation manual delivered with the kit.
And follow the conditions listed below.
•
Mount the REFNET joint so that it branches either horizontally or vertically.
•
Mount the REFNET header so that it branches horizontally.
햲
Horizontal surface
햳
With in 30° against horizontal surface
햴
Horizontal surface
7
The outside unit multi connection piping kit that is sold separately as an option (BHFP22MA56·84) is necessary for the multi installation of indoor
units. See the installation manual attached to the kit with attention to the following restrictions when installing.
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