Heat Insulation Of Piping - Daikin RXSQ24TAVJUA Installation Manual

• Insulation is required to all gas pipe.
• When the gas pipe diameter is larger than the specified pipe diam-
eter, add the amount of refrigerant according to "7-7 Additional
refrigerant charge amount" term.
• In order to maximize the performance, it is recommended to use
standard size piping and install insulation. On both liquid and gas
pipes.
• Main pipe: Main pipe means the field line set from the stop valve to
the first branch.
• Branch pipe: Branch pipe means the field line set from the first
branch to indoor units.
Main pipe
• In installations where existing refrigerant pipes are being used; and
the pipes are not accessible to the installer, ensure that all visible
piping is insulated. The refrigerant pipes between the outdoor unit
and wall must be insulated if any portion of the un-accessible liquid
pipe cannot be insulated. In addition to this, a field setting change
is required to enable to system to operate smoothly in such instal-
lations. Failure to follow the instruction may lead to damage due to
sweating and cause compressor damage and void warranty.
• In case of "no-insulation" on liquid line, when ambient temperature
is "low," the system may cycle the fan off for thermo-off unit and fan
only unit. While the off cycle is engaged, the thermostat will display
a temporary "standby" message until the system recovers from the
off cycle and the fan operation continues.
• The field setting for indoor units are also required. Selection of
thermistor is only remote controller thermistor. See the indoor
installation manual.
NOTE
Cutting out the two slits makes it possible to install as shown in figure 24.
(Use a metal saw to cut out the slits.)
<Precautions when connecting pipes>
• Please refer to the Table 1 for the dimensions for processing flares.
• When connecting the flare nut, coat the flare both inside and outside
with refrigerating machine oil and initially tighten by hand 3 or 4 turns
before tightening firmly.
• Please refer to the Table 1 for the tightening torque. (Too much tight-
ening will end up in splitting of the flare.)
Table 1
A dimen-
Pipe size Tightening sions for
(in.) torque (ft·lbf) processing
flares (in.)
3/8"
24.1~29.4 0.504~0.520
(9.5mm) (32.7~39.9N·m) (12.8~13.2mm)
5/8"
45.6~55.6 0.760~0.776
(15.9mm) (61.8~75.4N·m) (19.3~19.7mm)
Refrigerant oil
English
Branch pipe
Flare shape (in.)
R0.016~0.031
(0.4~0.8mm)
• If a torque wrench is not available, there is a place where the tight-
ening torque will suddenly increase if a normal wrench is used to
tighten the flare nut.
From that position, further tighten the flare nut the angle shown below.
Pipe size Further tightening angle
3/8"
60°~ 90 °
(9.5mm)
5/8"
30°~ 60°
(15.9mm)
• After all the piping has been connected, use nitrogen to perform a
gas leak check.
Precautions for connecting pipes
• Be careful not to let the interunit piping come into contact with the
compressor terminal cover.
Adjust the height of the insulation material on liquid pipe when it has the
possibility of getting in contact with the terminal. Also make sure that
the interunit piping does not touch the mounting bolt of the compressor.
(Refer to figure 25)
1. Compressor
2. Corking, etc.
3. Insulation material
4. Bolts
5. Interunit piping
• If installing the outdoor unit higher than the indoor unit, caulk the
space around insulation and tubes because condensation on the
check valve can seep through to the indoor unit side.
[Preventing foreign objects from entering]
• Plug the pipe through-holes with putty or insulating material (pro cured
locally) to stop up all gaps, as shown in figure 26. (Figure 26 indicates the
forward case. Do the same in case of other directions.) Insects or small
animals entering the outdoor unit may cause a short in the control box.
(Refer to figure 26)
1. Putty or insulating material
2. (field supply)
Refer to BHL-02A IO when brazing vessel kit to the system.

7-5 Heat insulation of piping

• Highly recommended to insulate the interunit piping (liquid and gas-side)
and the refrigerant branch kit. (Not insulating them may cause leaking.)
• The insulation dimension is recommended as following:
Ambient temperature: 86°F (30°C),
humidity : Below 80% RH
Minimum thickness : 9/16 inch
(15mm)
• When using commercial copper pipes and fittings, observe the following:
a)Insulation of pipes should be done after performing air tight test
and vacuum drying on page 12.
b)Heat transfer rate: 0.041 to 0.052W/Mk (0.024 to 0.030BTU/fth°F
(0.035 to 0.045kcal/mh°C))
c)Be sure to use insulation that is designed for use with HVAC Sys-
tems.
d)The highest temperature that the gas-side piping can reach is
around 248°F(120°C), so be sure to use insulating material which
is very resistant.
(The highest temperature that the gas-side piping can reach is around
248°F(120°C), so be sure to use insulating material which is very resis-
tant.)
CAUTION
For local insulation, be sure to insulate all the way to the pipe con-
nections inside the machine.
Exposed piping may cause leaking or burns on contact.
Recommended arm length
of tool (in.)
Approx. 7 7/8 (200mm)
Approx. 11 13/16 (300mm)
Ambient temperature: 86°F (30°C),
humidity : 80% RH and above
Minimum thickness : 3/4 inch
(20mm)
9