Installation Requirements; Torque Requirements; Pipe Length And Elevation - Lennox MCFA Service Manual

18. Installation Requirements

18.1. Torque Requirements

Refrigerant pipe diameter is different according to indoor unit to be connected. When using the extension pipe, refer to
the tables below.
When refrigerant pipe diameter is different from that of the outdoor unit connector (18K indoor unit) an additional adapter
is required.
Outside Diameter
MM
Ф6.35
Ф9.52
Ф12.7

18.2. Pipe Length and Elevation

Maximum piping length and height difference.
Model
9K
12K and 18K
23K
CAUTION
Table 15. Torque
Inches
1/4
3/8
1/2
Table 16. Pipe Diameter - MM (Inches)
Indoor Unit
Pipe Diameter (mm/inches)
Liquid
Gas
Liquid
Gas
Liquid
Gas
1 drive 2
1 drive 3
1 drive 4
1 drive 5
Torque
v.cm
1500 (153kgf.cm)
2500 (255kgf.cm
3500 (357kgf.cm)
6.35 (1/4)
9.52 (3/8)
6.35 (1/4)
12.7 (1/2)
9.52 (3/8)
15.9 (5/8)
86
Additional Tightening
N.cm
1600 (163kgf.cm)
2600 (265kgf.cm)
3600 (367kgf.cm)
Extension Pipe Diameter (mm/inches)
Liquid
Gas
Liquid
Gas
Liquid
Gas
Liquid 6.35 (1/4) *2
Gas 9.52 (3/8) *2
Liquid 6.35 (1/4) *3
Gas 9.52 (3/8) *3
Liquid 6.35 (1/4) *4
9.52 (3/8) *3
Gas
12.7 (1/2) *1
Liquid 6.35 (1/4) *5
9.52 (3/8) *3
Gas
12.7 (1/2) *2
6.35 (1/4)
9.52 (3/8)
6.35 (1/4)
12.7 (1/2)
9.52 (3/8)
15.9 (5/8)