Daikin RZAG71L7V1B, Reference Manual

Page: 14 / 40

6 Installation
Installer reference guide
14
RZAG71~140L7V1B
Split system air conditioners
4P418663-1 – 2016.02
▪ Set the nitrogen pressure to 20 kPa (just enough so it can be felt
on the skin) with a pressure-reducing valve.
a b c d e
f
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.
6.4.7 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 illustration shows each part required in handling the
valve.
c
d
a
b
a Service port and service port cap
b Valve stem
c Field piping connection
d Stem cap
▪ Keep both stop valves open during operation.
▪ Do NOT apply excessive force to the valve stem. Doing so may
break the valve body.
▪ 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.
a
b
a Spanner
b Torque wrench
▪ 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.
Silicon sealant, make sure there is no gap.
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:
Counterclockwise to open.
Clockwise to close.
3 When the valve stem cannot be turned any further, stop turning.
The valve is now opened/closed.
To handle the stem cap
Take the following guidelines into account:
▪ The stem cap is sealed where indicated with the arrow. Do NOT
damage it.
▪ After handling the stop valve, make sure to tighten the stem cap
securely.
▪ For the tightening torque, refer to the following table.
▪ Check for refrigerant leaks after tightening the stem cap.
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
To handle the service cap
Take the following guidelines into account:
▪ 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, tighten the service port cap
securely. For the tightening torque, refer to the table in chapter
"To handle the stem cap" on page 14 .
▪ Check for refrigerant leaks after tightening the service port cap.
6.4.8 To connect the refrigerant piping to the
outdoor unit
▪ Piping length. Keep field piping as short as possible.
▪ Piping protection. Protect the field piping against physical
damage.
1 Do the following:
▪ Remove the service cover (a) with screw (b).
▪ Remove the piping intake plate (c) with screw (d).
c
a
b
d
2 Choose a piping route (a, b, c or d).