Refrigerant Piping Work - Daikin FXTQ12PAVJU Installation Manual

5.

REFRIGERANT PIPING WORK

〈Observe the requirements listed below for refrigerant
piping sizes.〉
Liquid
12 · 18 type 1/4 in.
24 · 30 · 36 ·
3/8 in.
42 · 48 · 54 type
〈Execute heat insulation work completely on both sides of
the gas piping and the liquid piping or else a water leak-
age might result.
Failing to insulate the pipes may cause leaking or burns.
And be sure to use the insulation which can withstand
such temperatures of 248°F or more for the equalizer pipe
and the gas piping. Reinforce the insulation on the refrig-
erant piping according to the installation environment. If
the temperature or humidity in the product installation
location might reach 86°F or 80%, respectively. Condensa-
tion may form on the surface of the insulation.〉
CAUTION
Follow the points at below.
• Use a tube cutter and fl are suitable for the type of refriger-
ant.
• To prevent dust, moisture or other foreign matter from infi l-
trating the piping, either pinch the end or cover it with tape.
• Do not allow anything other than the designated refrigerant
to get mixed into the refrigerant circuit, such as air. If any
refrigerant gas leaks while working on the unit, immediately
ventilate the room.
(1) Cut off the spin closure.
• The outdoor unit is charged with refrigerant.
• This coil contains gas under 150 P.S.I.G.
Release pressure from the gas piping pressure-release
device before initiating piping work.
Sharp object
(2) Push
Detail
Pressure
release device
Gas piping
Liquid piping
English
Gas
1/2 in.
5/8 in.
Cap
After the work is finished,
try to repair.
(1) Remove
Front panel
• Cut off the pipe end with a tube cutter.
(Both liquid line and gas line)
Cut with a tube cutter
(2) Connect the piping.
1. Remove the upper and lower front panels.
2. Slide the front panel (lower) along the fi eld piping until it
is far enough away that it will not be affected by heat
from brazing, as shown in Fig. 3.
3. Braze up to the fi eld piping fi tting port while cooling the
sensor and the thermal insulation.
4. Close the upper and lower front panels once heat from
the brazed areas has dissipated.
NOTE
• When brazing the fi eld piping, cover the pipe insulation and
the thermal sensor inside the insulation with a damp cloth to
prevent any damage to the sensor or the insulation. Other-
wise, the sensor may be damaged by heat of brazing, which
lead to a failure of normal operation.
Field piping fitting port (brazed)
Field piping
Fig. 3
(3) After the work is fi nished, make sure to check that
there is no gas leak.
(4) After checking for gas leaks, be sure to insulate the
piping connections referring to Fig. 4.
Do not leave a gap
Air
handler
Fig. 4
Gas piping
Piping heat insulation
material
Liquid piping
6