Refrigerant Piping Connections - Lennox MLA Series Installation & User's Instructions

Figure 15. Securing Outdoor Unit to Slab
Figure 16. Securing Outdoor Unit to Rails
Securing Outdoor Unit To Hanging Brackets
If the outdoor unit is installed on field-provided wall
mounting brackets, use lag bolts or equivalent to secure
the outdoor unit to the bracket. Minimum rear clearance
can be reduced to 6 inches (152 mm) when mounted
on brackets and with no obstructions on the other three
sides. Allow for condensate disposal when placing units
above one another.
Air Outlet
Figure 17. Securing Outdoor Unit to Brackets

Refrigerant Piping Connections

Line sets consists of two copper pipes connecting the
outdoor unit to the indoor unit. "Table 3. Refrigerant Piping
and Indoor Unit Connection Sizes" lists the connection
sizes. The connections are made using the provided brass
flare nuts at the end of the refrigerant piping connections.
1. Choose the correct pipe sizes for your application
using "Table 3. Refrigerant Piping and Indoor Unit
Connection Sizes" on page 12.
2. Confirm that you are using the correct diameter piping.
3. Determine the necessary piping length required for the
application.
4. Cut the selected pipes with a pipe cutter. Make the
cuts flat and smooth as illustrated in "Figure 18.
Four Field-provided Anchor Bolts
Four Field-Provided
Anchor Bolts
6 in
152 mm
Air Inlet
Cutting Pipe".
Figure 18. Cutting Pipe
5. Insulate the copper piping.
6. Insert a flare nut onto each pipe before flaring.
7. Use "Table 2. Flaring Piping" on page 11 to properly
flare the pipe.
Table 2. Flaring Piping
Flare Dimension
A (mm)
Pipe Diameter
Min
1/4" (6.35) 8.3
1/2" (9.52" 15.4
8. After flaring the pipe, temporarily sealed pipe ends with
adhesive tape to avoid contaminants from entering the
pipes.
9. The seal on the unit refrigerant piping connections
should remain in place until the last possible moment.
10. This will prevent dust or water from getting into the
refrigerant piping before it is connected.
11. CAREFULLY adjust refrigerant piping connections to
suit the application.
12. Slowly loosen one of the flare nuts to release the
factory nitrogen charge from the indoor units only.
13. Remove the flare nuts from the connections on the
unit and discard the seal from each of the piping
connections.
14. Slide the flare nuts onto the ends of the field-provided
refrigerant piping before using a suitable flaring tool to
flare the end of the copper pipe.
15. Apply recommended HFC-410A refrigerant lubricant
to the outside of the flared refrigerant lines.
11
Lean Crude Burr
Flare Shape
Max
- +
90 ° 4
8.7
A
15.8
R0.4~0.8