Line sets come in pre-insulated coils or are made up from soft or hard copper on the job. Their diameters and length affect oil return, pressure drop and refrigerant charge: manufacturers state a base length included in the factory charge and an amount to add per foot beyond it. Reusing an old line set with a different refrigerant means checking size, cleanliness and flush requirements.
Line set's 45 feet and the factory charge covers 15, so weigh in another 18 ounces at 0.6 per foot.
Also heard as
- lineset
- refrigerant lines
- the lines
Related terms
Mini-split
A ductless split system with an outdoor inverter unit connected to one or more indoor heads by refrigerant lines.
Weigh in
To charge a system with a measured weight of refrigerant on a scale, set by nameplate charge and line set length.
Sweat
To join copper pipe and fittings with a torch and filler metal drawn into the joint by capillary action.
Flowing nitrogen
Running a low flow of dry nitrogen through copper lines while brazing to keep oxide scale from forming inside.