Ductless mini-split systems are increasingly popular for their efficiency and flexibility. This guide covers the key installation considerations.
Line Set Sizing
Proper line set sizing is critical for system performance:
- 9,000-12,000 BTU: 1/4" liquid, 3/8" suction
- 18,000-24,000 BTU: 1/4" liquid, 1/2" suction
- 36,000+ BTU: 3/8" liquid, 5/8" suction
Maximum Line Set Length
Most manufacturers allow 50-75 feet without additional refrigerant. Check your specific model's installation manual.
Electrical Requirements
- Dedicated circuit required
- Disconnect switch within sight of outdoor unit
- Properly sized breaker per manufacturer specs
Common Installation Mistakes
- Not evacuating the lines properly (minimum 500 microns)
- Kinking line sets during installation
- Improper drainage pitch (need 1/4" per foot minimum)
- Not using proper flaring tools
Get the Right Equipment
PES Supply stocks MRCOOL, Samsung, LG, and Mitsubishi mini-splits with fast shipping. Our tech team can help you spec the right system for any application.