Ductless Mini-Split Guide: Is It Right for Your Home?
Mini-splits have grown popular for room additions, older homes, and supplemental cooling. Here's everything you need to know about this versatile technology.
Ductless mini-split systems have become increasingly popular, but they're not the right solution for every situation. Let's break down when they make sense.
How Mini-Splits Work
A mini-split has two main components: - An outdoor compressor/condenser unit - One or more indoor air handling units
They're connected by refrigerant lines, not ductwork. Each indoor unit heats or cools its zone independently.
Where Mini-Splits Excel
Room Additions Adding ductwork to a new room can be expensive and complicated. A mini-split provides climate control without major construction.
Older Homes Without Ducts Many Bay Area homes from the early 1900s have no ductwork. Mini-splits add AC and modern heating without invasive duct installation.
Garage Conversions Converting a garage to living space? A mini-split is often the simplest HVAC solution.
Hot/Cold Rooms That one room that's always too hot or too cold? A mini-split can supplement your central system.
Home Offices If you're working from home, a dedicated mini-split lets you heat or cool your workspace without conditioning the whole house.
Advantages
- **Efficiency:** No duct losses means more efficient operation
- **Zoning:** Heat or cool only occupied spaces
- **Flexibility:** Add units where needed
- **Quiet:** Indoor units are typically very quiet
- **Dual function:** Most provide both heating and cooling
Disadvantages
- **Aesthetics:** The indoor unit is visible on your wall
- **Cost per unit:** More expensive than equivalent ducted capacity
- **Multiple units needed:** One unit per zone adds up
- **Maintenance:** Each indoor unit needs regular cleaning
- **Not ideal for whole-home:** Central systems are usually more economical for conditioning an entire house
Installation Considerations
- Outdoor unit needs proper placement for airflow and appearance
- Refrigerant lines must be run between indoor and outdoor units
- A small hole (about 3") is needed through the wall
- Electrical requirements vary by capacity
Sizing
Mini-splits are rated in BTUs. General guidelines: - 150-250 sq ft: 6,000-9,000 BTU - 250-450 sq ft: 9,000-12,000 BTU - 450-700 sq ft: 12,000-18,000 BTU - 700-1,000 sq ft: 18,000-24,000 BTU
Proper sizing depends on insulation, sun exposure, and other factors.