To Braze The Pipe End; Using The Stop Valve And Service Port - Daikin SERHQ020BAW1 Installer And User Reference Manual

6 Installation
6.5.2

To braze the pipe end

NOTICE
Precautions when connecting field piping. Add brazing
material as shown in the figure.
≤Ø25.4
1
1
▪ 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.
a b
f
a Refrigerant piping
b Part to be brazed
c Taping
d Manual valve
e Pressure-reducing valve
f Nitrogen
▪ Do NOT use anti-oxidants when brazing pipe joints.
Residue can clog pipes and break equipment.
▪ Do NOT use flux when brazing copper-to-copper refrigerant
piping. Use phosphor copper brazing filler alloy (BCuP), which
does not require flux.
Flux has an extremely harmful influence on refrigerant piping
systems. For instance, if chlorine based flux is used, it will cause
pipe corrosion or, in particular, if the flux contains fluorine, it will
deteriorate the refrigerant oil.
6.5.3

Using the stop valve and service port

To handle the stop valve
Take the following guidelines into account:
▪ The stop valves are factory closed.
▪ The following illustrations show each part required in handling the
valve.
a
b
c
d
a Service port and service port cover
b Stop valve
c Field piping connection
d Stop valve cover
a b
e d c
Installer and user reference guide
20
>Ø25.4
1
2 2
1
c d e
f
a Service port
b Stop valve cover
c Hexagon hole
d Shaft
e Seal
▪ Keep both stop valves open during operation.
▪ Do NOT apply excessive force to the stop valve. Doing so may
break the valve body.
To open/close the stop valve
1 Remove the stop valve cover.
2 Insert a hexagon wrench (liquid side: 4 mm, gas side: 8 mm)
into the stop valve and turn the stop valve:
Counterclockwise to open.
Clockwise to close.
3 When the stop valve CANNOT be turned any further, stop
turning. The valve is now open/closed.
INFORMATION
▪ The SERHQ020 supports Ø22.2 field piping on the
accessory pipe supplied with the unit.
▪ The SERHQ032 supports Ø28.6 field piping on the
accessory pipe supplied with the unit.
To handle the service port
Location of service ports
For the service port location, refer to the "Caution" label attached on
the front panel of the outdoor unit.
▪ Always use a charge hose equipped with a valve depressor pin,
since the service port is a Schrader type valve.
▪ After handling the service port, make sure to tighten the service
port cover securely. For the tightening torque, refer to the table
below.
▪ Check for refrigerant leaks after tightening the service port cover.
Tightening torques
Stop valve Tightening torque N•m (turn clockwise to close)
size (mm)
Valve body Hexagonal
wrench
Ø9.5 5.4~6.6 4 mm
Ø12.7 8.1~9.9
Ø25.4 27.0~33.0 8 mm
SERHQ020~032BAW1 + SEHVX20~64BAW
Shaft
Cap (valve Service
lid) port
13.5~16.5 11.5~13.9
18.0~22.0
22.5~27.5
Split packaged air-cooled water chiller
4P508020-1B – 2018.04