Daikin FTXK25AV1BW Manuel D'installation page 12

Allowable Piping Length
If the pipe is too long, both the capacity and reliability of the unit will drop. As the number of bends increases, resistance to
the flow of refrigerant system increases, thus lowering cooling capacity. As a result, the compressor may become defective.
Always choose the shortest path and follow the recommendations as tabulated below:
Indoor
Model
Outdoor
Min. Allowable Length (L), m
Max. Allowable Length (L), m
Max. Allowable Elevation (E), m
Gas Pipe Size, mm/(in)
Liquid Pipe Size, mm/(in)
Be sure to add the proper amount of additional refrigerant. Failure to do so may result in reduced performance.
*
Remark: The refrigerant pre-charged in the outdoor unit is for piping length up to 7.5m.
Equivalent length for various fitting (meter)
Pipe Size
3/8" (OD9.52mm)
1/2" (OD12.7mm)
5/8" (OD15.9mm)
3/4" (OD19.1mm)
7/8" (OD22.2mm)
1" (OD25.4mm)
1 1/8" (OD28.6mm)
1 3/8" (OD34.9mm)
Notes:
1. Equivalent piping length is obtained with actual length of gas piping.
2. 90° bend of piping is equivalent to L joint.
Bending must be carefully made so as not to crush the pipe. Use a pipe bender to bend a pipe where possible.
REFRIGERANT PIPING
Indoor unit
Outdoor Unit
(FTXK) 25
(RXK) 25
L joint
0.18
0.20
0.25
0.35
0.40
0.45
0.50
0.60
1-10
L E
35
35
3
20
10
9.52 (3/8")
6.35 (1/4")
50 60
50 60
3
30
10
12.70 (1/2") 15.88 (5/8")
6.35 (1/4")
Trap bend
1.3
1.5
2
2.4
3
3.4
3.7
4.4