Lennox MWHA009S4, Service Manual

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Table 4. Line Set Guide
Each system size has a line set length and vertical elevation parameters.
System
Size (KBtu)
Line Set Diameters (in.)
Maximum Elevation
Outdoor Unit BELOW
Indoor Unit - Feet
(Meter)
Maximum
Elevation
Outdoor Unit
ABOVE Indoor
Unit - Feet (Meter)
Maximum Line
Set Length -
Feet (Meters)
Additional Refrigerant for greater
than 25 Foot Line Set Lenght
Liquid Gas
009 1/4 3/8 33 (10) 33 (10) 82 (25)
For the additional charging, we
recommend 0.161 oz. for 1/4” liquid
line and 0.322 oz. for 3/8” liquid line
per foot.
012 1/4 1/2 33 (10) 33 (10) 82 (25)
018 1/4 1/2 66 (20) 66 (20) 98 (30)
024 3/8 5/8 66 (20) 66 (20) 98 (30)
9. Outdoor Unit Connections and Line Set
Usage
Description
Catalog
No.
Size
09 12 18 24
OUTDOOR UNIT
Line Sets 1/4 in. x 3/8 in. x 25 ft.
90X53 •
N/A
1/4 in. x 3/8 in. x 50 ft. X0258 • N/A
1/4 in. x 1/2 in. x 25 ft. 90X52 N/A • • N/A
1/4 in. x 1/2 in. x 50 ft. X0259 N/A • • N/A
3/8 in. x 5/8 in. x 25 ft. X8406 N/A •
3/8 in. x 5/8 in. x 50 ft. X8407 N/A •
9.1. Pipe Length
Maximum piping length and height difference.
Table 5. Pipe Diameter - MM (Inches)
Indoor Unit
Extension Pipe Diameter (mm/inches)
Model Pipe Diameter (mm/inches)
9K
Liquid 6.35 (1/4) Liquid 6.35 (1/4)
Gas 9.52 (3/8) Gas 9.52 (3/8)
12K and 18K
Liquid 6.35 (1/4) Liquid 6.35 (1/4)
Gas 12.7 (1/2) Gas 12.7 (1/2)
24K
Liquid 9.52 (3/8) Liquid 9.52 (3/8)
Gas 15.9 (5/8) Gas 15.9 (5/8)
9.2. Torque Requirements
CAUTION
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.
Table 6. Torque
Outside Diameter Torque Additional Tightening
MM Inches v.cm N.cm
Ф6.35 1/4 1500 (153kgf.cm) 1600 (163kgf.cm)
Ф9.52 3/8 2500 (255kgf.cm 2600 (265kgf.cm)
Ф12.7 1/2 3500 (357kgf.cm) 3600 (367kgf.cm)