Caution On Piping Handling; Selection Of Copper And Heat Insulation Materials - Daikin FTXG25JV1BW Installation Manual

Refrigerant Piping Work
2.
Refrigerant piping
CAUTION
• Use the flare nut fixed to the main unit. (To prevent cracking of the flare nut by aged deterioration.)
• To prevent gas leakage, apply refrigeration oil only to the inner surface of the flare. (Use refrigeration oil for R410A.)
• Use torque wrenches when tightening the flare nuts to prevent damage to the flare nuts and gas leakage.
Align the centres of both flares and tighten the flare nuts 3 or 4 turns by hand. Then tighten them fully with the torque wrenches.
Do not apply refrigeration
oil to the outer surface.
Flare nut
Do not apply refrigeration
oil to the flare nut avoid
tightening with over torque.

2-1. Caution on piping handling

1) Protect the open end of the pipe against dust and moisture.
2) All pipe bends should be as gentle as possible. Use a pipe bender
for bending.

2-2. Selection of copper and heat insulation materials

• When using commercial copper pipes and fittings, observe the following:
1) 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.
2) Be sure to insulate both the gas and liquid piping and to provide insulation
dimensions as below.
25/35 class
O.D. 9.5mm
30mm or more
3) Use separate thermal insulation pipes for gas and liquid refrigerant pipes.
7
[Apply oil]
Flare nut tightening torque
Gas side
3/8 inch
32.7-39.9N•m
(330-407kgf•cm)
Gas side
50 class
O.D. 6.4mm
O.D. 12.7mm
Minimum bend radius
40mm or more 30mm or more
Thickness 0.8mm (C1220T-O)
Apply refrigeration
oil to the inner
surface of the flare.
Spanner
Piping union
Liquid side
1/2 inch 1/4 inch
49.5-60.3N•m 14.2-17.2N•m
(505-615kgf•cm) (144-175kgf•cm)
Liquid side Gas pipe thermal insulation
25/35 class
I.D. 12-15mm
[Tighten]
Torque wrench
Flare nut
Be sure to
place a cap.
Rain
If no flare cap is
available, cover the
flare mouth with
tape to keep dirt or
water out.
Inter-unit wire
Gas pipe
Gas pipe
insulation
Finishing tape
thermal insulation
50 class
I.D. 14-16mm
Thickness 10mm Min.
Wall
Liquid pipe
Liquid pipe
insulation
Drain hose
Liquid pipe
I.D. 8-10mm
IEnglish