Guidelines When Connecting The Refrigerant Piping; Pipe Bending Guidelines; To Flare The Pipe End; To Braze The Pipe End - Daikin Altherma EHVH08SU18CB6W Installer's Reference Manual

NOTICE
Take the following precautions on refrigerant piping into
account:
▪ Avoid anything but the designated refrigerant to get
mixed into the refrigerant cycle (e.g. air).
▪ Only use R410A when adding refrigerant.
▪ Only use installation tools (e.g. manifold gauge set) that
are exclusively used for R410A installations to
withstand the pressure and to prevent foreign materials
(e.g. mineral oils and moisture) from mixing into the
system.
▪ Install the piping so that the flare is NOT subjected to
mechanical stress
▪ Protect the piping as described in the following table to
prevent dirt, liquid or dust from entering the piping.
▪ Use caution when passing copper tubes through walls
(see figure below).
Unit Installation period
Outdoor unit >1 month
<1 month
Indoor unit Regardless of the
period
INFORMATION
Do NOT open the refrigerant stop valve before checking
the refrigerant piping. When you need to charge additional
refrigerant it is recommended to open the refrigerant stop
valve after charging.
7.5.3 Guidelines when connecting the
refrigerant piping
Take the following guidelines into account when connecting pipes:
▪ Coat the flare inner surface with ether oil or ester oil when
connecting a flare nut. Tighten 3 or 4 turns by hand, before
tightening firmly.
▪ ALWAYS use 2 wrenches together when loosening a flare nut.
▪ ALWAYS use a spanner and torque wrench together to tighten the
flare nut when connecting the piping. This to prevent nut cracking
and leaks.
a b
c
d
a Torque wrench
b Spanner
c Piping union
d Flare nut
ERLQ004~008CA + EHVH04+08SU18+26CB6W
Daikin Altherma – Low temperature split
4P449978-1B – 2018.07
Piping size
7.5.4
Use a pipe bender for bending. All pipe bends should be as gentle
as possible (bending radius should be 30~40 mm or larger).
7.5.5
1 Cut the pipe end with a pipe cutter.
2 Remove burrs with the cut surface facing down so that the
Protection method
Pinch the pipe
a
Pinch or tape the pipe
3 Remove the flare nut from the stop valve and put the flare nut
4 Flare the pipe. Set exactly at the position as shown in the
A
5 Check that the flaring is properly made.
a
7.5.6
The indoor unit and outdoor unit have flare connections. Connect
both ends without brazing. If brazing should be needed, take the
following into account:
▪ When brazing, blow through with nitrogen to prevent creation of
large quantities of oxidised film on the inside of the piping. This
film adversely affects valves and compressors in the refrigerating
system and prevents proper operation.
▪ Set the nitrogen pressure to 20 kPa (0.2 bar) (just enough so it
can be felt on the skin) with a pressure-reducing valve.
Tightening
(mm) torque (N•m) dimensions (A)
Ø6.4 15~17
Ø15.9 63~75

Pipe bending guidelines

To flare the pipe end

CAUTION
▪ Incomplete flaring may cause refrigerant gas leakage.
▪ Do NOT re-use flares. Use new flares to prevent
refrigerant gas leakage.
▪ Use flare nuts that are included with the unit. Using
different flare nuts may cause refrigerant gas leakage.
chips do NOT enter the pipe.
b
a Cut exactly at right angles.
b Remove burrs.
on the pipe.
following figure.
A
Flare tool for Conventional flare tool
R410A (clutch
Clutch type
type)
(Ridgid-type)
0~0.5 mm 1.0~1.5 mm
b
c
a Flare's inner surface MUST be flawless.
b The pipe end MUST be evenly flared in a perfect circle.
c Make sure the flare nut is fitted.

To braze the pipe end

7 Installation
Flare Flare shape
(mm)
(mm)
90° ±2
8.7~9.1
A
19.3~19.7
R=0.4~0.8
Wing nut type
(Imperial-type)
1.5~2.0 mm
Installer reference guide
35