Installer reference guide
31
08 + ERLQ004~008
Daikin Altherma - Low Temperature Split
4P313774-1 – 2012.05
7 Installation
5
Check that the flaring is properly made.
7.4.3 To braze the pipe end
The indoor unit and outdoor unit have flare connections. Connect
both ends without brazing. If brazing should be needed, take the
following into account:
Q
When brazing, blow through with nitrogen to prevent creation of
large quantities of oxidized film on the inside of the piping. This
film adversely affects valves and compressors in the
refrigerating system and prevents proper operation.
Q
Set the nitrogen pressure to 20 kPa (just enough so it can be felt
on the skin) with a pressure-reducing valve.
Q
Do NOT use anti-oxidants when brazing pipe joints.
Q
Do NOT use flux when brazing copper-to-copper refrigerant
piping. Use phosphor copper brazing filler alloy (BCuP), which
does not require flux.
7.4.4 To handle the stop valve
Take the following guidelines into account:
Q
The stop valves are factory closed.
Q
The following illustration shows each part required in handling
the valve.
Q
Keep both stop valves open during operation.
Q
Do NOT apply excessive force to the valve stem. Doing so may
break the valve body.
Q
Always make sure to secure the stop valve with a spanner, then
loosen or tighten the flare nut with a torque wrench. Do NOT
place the spanner on the stem cap, as this could cause a
refrigerant leak.
Q
When it is expected that the operating pressure will be low (e.g.
when cooling will be performed while the outside air temperature
is low), sufficiently seal the flare nut in the stop valve on the gas
line with silicon sealant to prevent freezing.
7.4.5 To open/close the stop valve
1
Remove the valve cover
2
Insert a hexagon wrench (liquid side: 4 mm, gas side: 6 mm) into
the valve stem and turn the valve stem:
3
When the valve stem cannot be turned any further, stop turning.
The valve is now opened/closed.
7.4.6 To handle the stem cap
Take the following guidelines into account:
Q
The stem cap is sealed where indicated with the arrow. Do NOT
damage it.
Q
After handling the stop valve, make sure to tighten the stem cap
securely.
Q
For the tightening torque, refer to the following table.
Q
Check for refrigerant leaks after tightening the stem cap.
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 lifted.
a
Refrigerant piping
b
Part to be brazed
c
Taping
d
Manual valve
e
Pressure-reducing valve
f
Nitrogen
a
Service port and service port cap
b
Valve stem
c
Field piping connection
d
Stem cap
a
b
c
a
b
c
d
e
f
f
c
d
a
b
a
Spanner
b
Torque wrench
Silicon sealant, make sure there is no gap.
Counterclockwise to open.
Clockwise to close.
Item
Tightening torque (N·m)
Stem cap, liquid side
13.5~16.5
Stem cap, gas side
22.5~27.5
Service port cap
11.5~13.9
a
b
