Standard Split System Line Sets

Line sets consist of two semi-flexible copper pipes to connect the outdoor air conditioner or heat pump to the indoor evaporator coil. The smaller pipe is called the liquid line. The larger pipe is referred to as the suction line, and includes insulation. The liquid line diameter for all standard residential systems is 3/8 inches in diameter. The suction line diameter will be either 3/4, 7/8 or 1 1/8 inches, depending on the size and efficiency of the air conditioner or heat pump. Line sets come in several lengths and are designed to be cut to fit your exact need.

When purchasing refrigeration lines, measure the length of line set needed to connect your outdoor condenser to the indoor forced air equipment. Based on that length, the correct size diameter line set can be selected which will ensure your system meets the listed SEER rating and capacity. Once you have accurately measured the length needed, use our chart below to find the diameter best for your system.

For extended compressor life, if you're running a line set longer than 80 feet you'll need the following accessories:

• Crankcase Heater - This will minimize the risk of oil migration during the off cycle.
• TXV (Thermostatic Expansion Valve) - This will auto regulate a refrigerant subcooling of around 6° which is ideal for a long lineset.
• Hard-Start Capacitor - This will help the compressor during startup with the extra work required from an increased refrigerant charge level. 

Want to cover up the line set outside your home so it blends in with your home's exterior? Check out our line set covers which will hide the line set and preserve your home's tidy look.