Hitachi RAS-18FSXNS2E - Size of Pipes (Ø MM)

14
PMML0628 rev.0 - 05/2023
3
PIPE SIZE SELECTION
PIPING WORK AND REFRIGERANT CHARGE
• The copper pipe for refrigeraon installaons is especially treated for outdoors and indoors. The
interior surface nish makes it easier for the refrigerant to circulate and withstands the acon of
the lubricant oil applied to outdoor equipment.
Always use clean copper pipes with no signs of knocks or cracks. Make sure there is no dust or
dampness on the inside. Before you install the pipes, clean the inside with oxygen-free nitrogen
gas to eliminate any remains of dust or other substances.
! CAUTION
• Do not use hand saws, circular saws, abrasive grinders or other tools that generate shavings.
• Strictly follow naonal or local regulaons regarding occupaonal health and safety.
• Wear appropriate means of protecon during cung or brazing operaons and installaon
(gloves, eye protecon, etc).
On compleng the installaon of the refrigerant pipes, insulate them appropriately using suitable
insulang material and seal the open space between the holes made and the pipe.
3.2.1 Size of pipes (Ø mm)
◆ For heat pump systems (2 pipe)
For selecng the pipe sizes between the outdoor unit and the piping connecon kit 1, between the
piping connecon kit 2 and for piping connecon kit Ⓐ, refer to the print version of the manual.
Combinaon of 2 and 3 units
1
2
1 1
A
A
Outdoor
Unit
A
Upstream Side
Outdoor
Unit
B
Outdoor
Unit
C
La Lb Lc
Piping Connecon
Kit 2
Piping Connecon
Kit 1
L
L
L: Keep the straight line distance of 500mm or more aer the piping connecon kit.