Black Box CRDX-W-FS-24KW Refrigerant Pipe Sizing, Remote Air-Cooled Condensers, Installation

*Equivalent feet accounts for the linear pipe length as well as equivalent length of valves, elbows, and tees as shown in the

previous table.

Table 2-7. Recommended liquid line sizes.

*Equivalent Length Ft.

Model Number

Chapter 2: Installation

2.8.1.2 Refrigerant Pipe Sizing

Refrigerant lines for split systems must be sized according to the piping distance between the evaporator and the condenser. Each valve, fitting, and bend in the refrigerant line must be considered in this calculation. Pipe sizes are given for “equivalent feet,” not linear feet. Do not confuse the terminologies. For example, a 7⁄8" standard 90° elbow has an equivalent length of 1.5 feet; a 7⁄8" branch tee has an equivalent length of 3.5 feet. These corrections must be accounted for when sizing your piping.

NOTE: Refrigerant piping between the Cold Row unit and the remote condenser must not exceed 150 feet (total equivalent length). The maximum level drop from the Cold Row unit to the condenser must not exceed 20 feet.

NOTE: Consult ASHRAE standards and refer to the Copeland applications data guide for more detailed information regarding refrigerant line traps and line sizing.

Refer to the following table for standard equivalent lengths, in feet, of straight pipe.

Table 2-5. Equivalent length of straight pipe.

OD (in.) Line Size	Globe Valve	Angle Valve	90° Elbow	45° Elbow	Tee Line	Tee Branch
1⁄2	9.0	5.0	0.9	0.4	0.6	2.0
5⁄8	12	6.0	1.0	0.5	0.8	2.5
7⁄8	15	8.0	1.5	0.7	1.0	3.5
11⁄8	22	12	1.8	0.9	1.5	4.5
13⁄8	28	15	2.4	1.2	1.8	6.0

Oil traps must be included every 20 feet in the vertical risers, and the refrigerant lines must be sloped 1⁄4 inch for every 10 feet in the horizontal lines to ensure proper oil return to the compressor. An inverted trap is required on the discharge line of the remote condenser to help prevent oil and liquid from flooding back to the compressor.

2.8.2 Remote Air-Cooled Condensers

Refer to the Recommended Discharge Line and Liquid Line sizing tables below. Systems using air-cooled condensers must not have a refrigerant line pressure drop over 14 psig across the condenser and the interconnecting piping to the condenser.

NOTE: Ensure proper condenser selection to maintain reasonable sub-cooling temperatures.

Table 2-6. Recommended discharge line sizes.

*Equivalent Length Ft.

	50 ft.. or less	100 ft. or less	150 ft. or less
CRDX-A-FS-12KW	5⁄8	5⁄8	5⁄8
CRDX-A-FS-24KW	7⁄8	7⁄8	7⁄8

Model Number
	50 ft.. or less	100 ft. or less	150 ft. or less
CRDX-A-FS-12KW	1 ⁄2	1 ⁄2	1 ⁄2
CRDX-A-FS-24KW	5⁄8	5⁄8	5⁄8

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