Allied Air Enterprises 4AC16LT manual Installing Refrigerant Line, Placement, Line Set Isolation

Select line set diameters from Table 2 to ensure that oil return to the compressor. Size vertical suction riser to maintain minimum velocity at minimum capacity. Recommended line length is 50’ or less. If more than 50’ line set is required, contact Technical Service.

Table 2 shows the diameters for line sets up to 100’ although vertical lift applications and trapping requirements need to be reviewed with Technical Service for line sets over 50’.

Refrigerant Line Set Diameters (in.)

Liquid Line

Line S et Length and S ize

BTUH

	12 ft. 25 ft. 50 ft. 75 ft. 100 ft.
24,000	3/8	3/8	3/8	3/8	3/8
36,000	3/8	3/8	3/8	3/8	1/2
48,000	3/8	3/8	3/8	1/2	1/2

60,000 3/8 3/8 3/8 1/2 1/2

S uction L ine

L ine S et L ength and S ize

B T U H

	12 ft. 25 ft. 50 ft. 75 ft. 100 ft.
24,000	3/4	3/4	3/4	3/4	7/8
36,000	7/8	7/8	7/8	7/8	1-1/8
48,000	7/8	1-1/8	1-1/8	1-1/8	1-1/8

60,000 1-1/8 1-1/8 1-1/8 1-1/8 1-1/8

For installations exceeding 50’, contact

Technical Services.

Table 2

WARNING

Polyolester (POE) oils used with R-410A refrigerant absorb moisture very quickly. It is very important that the refrigerant system be kept closed as much as possible. DO NOT remove line set caps or service valve stub caps until ready to make connections.

Installing Refrigerant Line

During the installation of an air conditioning system, it is important to properly isolate the refrigerant line to prevent unnecssary vibration. Line set contact with the structure (wall, ceiling, or floor) may cause objectionable noise when vibration is translated into sound. As a result, more energy or vibration can be expected. Close attention to line set isolation must be observed. If refrigeration lines are routed through a wall, seal and isolate the opening so vibration is not transmitted to the building.

Following are some points to consider when placing and installing a high-efficiency outdoor unit:

Placement

Be aware that some localities are adopting sound ordinances based on how noisy the unit is at the neighbor’s home, not at the original installation. Install the unit as far as possible from the property line. When possible, do not install the unit directly outside a bedroom window. Glass has a verry high level of sound transmission. Figure 4 shows how to place the outdoor unit and line set to reduce line set vibration.

Line Set Isolation

Illustrations on the pages 6 and 7 demonstrate procedures which ensure proper refrigerant line set isolation. Figure 6 shows how to install line sets on horizontal runs. Figure 7 shows how to make a transition from horizontal to vertical. Figure 9 shows how to install line sets on vertical runs.

Brazing Connection Procedure

1.Cut ends of refrigerant lines square (free from nicks or dents). Debur the ends. The pipe must remain round; do not pinch end of line.

2.Before making line set connections, use dry nitrogen to purge the refrigerant piping. This will help to prevent oxidation and the introduction of moisture into the system.

3.Use silver alloy brazing rods (5% or 6% silver alloy for copper-to-copper brazing or 45% silver alloy for

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