How to determine line set length for your HVAC system?

The line set length for your HVAC system, specifically for a ductless mini-split system, is determined by the distance between the indoor air handler unit and the outdoor condenser unit. To define the appropriate line set length, follow these steps:

  1. Choose the installation locations: Determine where you want to install the indoor air handler and the outdoor condenser. Ensure that the chosen locations comply with any local codes or regulations and meet the manufacturer's installation requirements.

  2. Measure the distance: Measure the straight-line distance between the indoor and outdoor units. Keep in mind that the lines may need to run through walls, ceilings, or other obstacles, so you may need to account for additional length to accommodate these factors.

  3. Consider elevation differences: If there is a significant height difference between the indoor and outdoor units, account for the vertical distance when calculating the line set length. Be sure to check the manufacturer's guidelines regarding maximum allowed elevation difference to ensure proper system operation.

  4. Add extra length: It's always a good idea to add some extra length to your calculated measurement to account for any unforeseen obstacles, bends, or turns that may occur during installation. A typical recommendation is to add 10-15% extra length.

  5. Ask us! You can call us for help to 725 777 5484 or send us an email to The chat function is also available on the bottom right corner during business hours.

Once you have determined the appropriate lineset length, you can purchase the necessary materials for your HVAC installation. Remember that professional installation is recommended for ductless mini-split systems to ensure proper functioning and adherence to warranty requirements.

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