Refrigerant Piping; Refrigerant Piping Work - Daikin FTXZ25NV1B Installation Manual

Outdoor Unit Installation
4.

Refrigerant piping

CAUTION
• Use the fl are nut fi xed to the main unit. (To prevent cracking of the fl are nut by aged deterioration.)
• To prevent gas leakage, apply refrigeration oil only to the inner surface of the fl are. (Use refrigeration oil for R32.)
• Use torque wrenches when tightening the fl are nuts to prevent damage to the fl are nuts and gas leakage.
• Align the centres of both fl ares and tighten the fl are nuts 3 or 4 turns by hand. Then tighten them fully with the torque wrenches.
• Refrigerant oil for R410A can also be used for application to the inner fl are.
Apply oil
Do not apply
refrigeration oil to
the outer surface.
Flare nut
Do not apply refrigeration oil to
the fl are nut to avoid tightening
with excessive torque.
5.

Refrigerant piping work

5-1 Cautions on pipe handling
• Protect the open end of the pipe against dust and moisture.
• All pipe bends should be as gentle as possible. Use a pipe
bender for bending.
5-2 Selection of copper and heat insulation materials
When using commercial copper pipes and fi ttings, observe the following:
• Insulation material: Polyethylene foam
Heat transfer rate: 0.041 to 0.052W/mK (0.035 to 0.045kcal/mh°C)
Refrigerant gas pipe's surface temperature reaches 110°C max.
Choose heat insulation materials that will withstand this temperature.
• Be sure to insulate both the gas and liquid piping and to provide insulation dimensions as below.
Seal the edge of the insulation
if there is a possibility that the
condensation from the stop valve
might drip onto the indoor unit
through the gap between the
insulation and the pipe.
• Use separate thermal insulation pipes for gas and liquid refrigerant pipes.
13 13
Apply refrigeration
oil to the inner
Spanner
surface of the
fl are. fl are.
Piping union Piping union
Gas side Liquid side
O.D. 9.5mm O.D. 6.4mm
Minimum bend radius
30mm or more
Thickness 0.8mm (C1220T-O)
Tighten
Torque wrench
32.7-39.9N · m
(333-407kgf · cm)
Flare nut Flare nut
Rain
Piping bundle diagram
Liquid pipe insulation
Liquid pipe
Gas pipe
Gas pipe insulation
Gas pipe thermal insulation
I.D. 12-15mm
Thickness 10mm Min.
Flare nut tightening torque
Gas side Liquid side
9.5mm 6.4mm
14.2-17.2N · m
(144-175kgf · cm)
Valve cap tightening torque
Gas side Liquid side
9.5mm 6.4mm
21.6-27.4N · m
(220-280kgf · cm)
Service port cap tightening torque
10.8-14.7N · m (110-150kgf · cm)
Be sure to place a cap.
If no fl are cap is
available, cover the
fl are mouth with tape
to keep dirt or water
out.
Inter-unit wire
G Humidifying hose
Finishing tape
Liquid pipe thermal
insulation
I.D. 8-10mm
Wall