B145812025F – MINISPLIT LINE SET

Insulated mini split line set, 25 ft, with a 1/4 in. liquid line and a 5/8 in. suction line. Both ends are pre-flared with flare nuts, and the pair is jacketed in 1/2 in. closed-cell insulation. This is an iCool line set — the part number reads as 1/4 x 5/8 lines, 1/2 in. insulation, 25 ft, flare nuts.

A line set is chosen by line diameter and length, not by equipment model — a 1/4 x 5/8 set fits any single-zone ductless system whose service valves are 1/4 in. liquid and 5/8 in. suction, which in practice means the larger single-zone systems. Check the valve sizes on your outdoor unit before ordering. Related lengths in the same family: B145812015F (15 ft) and B145812050F (50 ft). Specifications taken from the iCool published line set price sheet.

Specs

• BrandiCool (ICOOL Products USA)
• Length25 ft
• Liquid line1/4 in. OD
• Suction line5/8 in. OD
• Insulation1/2 in. closed-cell
• EndsPre-flared, with flare nuts
• Tubing materialCopper
• Ship weightApprox. 10 lb

How do I buy a line set for a mini split?

By line diameter and length, not by equipment model number. Look at the two stub-outs on the outdoor unit. Most 9k and 12k heads are 1/4 by 3/8, and larger heads move to 1/4 by 1/2 or 3/8 by 5/8. Measure the run including vertical rise and the bends, and buy a little long rather than a little short. Multi-zone systems size each branch on its own, so measure every run separately.

How tight should the flare nuts be?

Use a torque wrench. Common figures are roughly 13 to 18 ft-lbs on 1/4 inch, 25 to 30 on 3/8, and 36 to 46 on 1/2, but the install manual for your unit is the authority. A flare nut torqued by feel is the single most common leak on a mini split. Loose leaks, and overtightened crushes the flare seat and leaks too, except now you get to cut it off and re-flare.

How do I make a flare that will not leak?

Deburr the cut with the tube pointed down so shavings drop out, because a burr guarantees a leak. Slide the flare nut on before you flare, which everyone forgets exactly once. Use a tool with a depth stop, and for R-410A or A2L work an eccentric cone flaring tool beats a plain screw-down block. A drop of Nylog on the flare face and the threads helps it seat. Then torque it.

What is an anti-blowback adapter for?

Mini split service ports are 5/16 inch, so you need a 5/16 to 1/4 adapter to land a hose. The anti-blowback style has a shut-off built in, so when you break the hose loose you do not take a face full of refrigerant and oil off the depressor pin. Get the 90 degree version when the port sits tight against the cabinet.