How Long Does It Take to Install a Mini Split?
- Jayant Upadhyay
- Jul 16
- 5 min read
Mini split systems, also known as ductless air conditioners or heat pumps, have become increasingly popular across the U.S. due to their energy efficiency, quiet operation, and zoning flexibility. Whether you’re cooling a single room or retrofitting an entire home, one question always comes up: How long does it take to install a mini split system?
The short answer: A basic single-zone mini split typically takes 4 to 8 hours to install. Multi-zone systems, electrical upgrades, and complex placements may extend installation to 1–2 days.
In this guide, we’ll break down every aspect of mini split installation, including factors that affect the timeline, tools required, the step-by-step process, and helpful tips to ensure a smooth experience.
Table of Contents
What Is a Mini Split System?
A mini split system consists of two primary components:
Indoor air handler (wall-, ceiling-, or floor-mounted)
Outdoor condenser unit (compressor and fan)
They connect via a refrigerant line, drain hose, and electrical wiring, making mini splits ideal for retrofits, room additions, basements, garages, and older homes without ductwork.
Average Installation Time by Type
Mini Split Type | Estimated Installation Time |
Single-zone (1 room) | 4–8 hours |
Dual-zone (2 rooms) | 1 day (6–10 hours) |
Multi-zone (3–5 rooms) | 1.5 to 2 days |
Ceiling cassette or concealed | 1–2 days (requires more work) |
DIY mini split kits | 1 day (for experienced installers) |
Note: Install time can vary based on wall type, electrical setup, and line run distance.
Factors That Affect Installation Time
Number of zones – More air handlers = more wiring and refrigerant work
Distance between indoor and outdoor units – Long runs increase labor
Wall and surface type – Brick and concrete take longer to drill through
Accessibility – Attic installs or rooftop condensers add complexity
Electrical upgrades – Panel rewiring or new circuits may add 2–4 hours
Permit requirements – Can delay start or final inspection
Installer experience – Pros work faster and more efficiently
Pre-Installation Planning
Before you even begin, planning can make or break your schedule.
✅ What to Decide Ahead of Time:
Unit placement (interior and exterior)
Number of zones and room coverage
Voltage and amperage requirements
Line set routing
Drainage location
Permit application (if required in your area)
Step-by-Step Installation Timeline
Here’s what a typical single-zone mini split install looks like:
Step 1: Site Preparation (30–60 min)
Clear furniture or obstructions
Lay drop cloths
Confirm tools and unit inventory
Step 2: Mount Indoor Unit (1–2 hours)
Install mounting bracket
Drill wall hole for line set
Mount air handler to wall securely
Step 3: Set Outdoor Unit (30–60 min)
Place on concrete pad or wall bracket
Ensure unit is level and clear of debris
Connect line set through access hole
Step 4: Run Line Set and Drain Hose (1–2 hours)
Route insulated copper refrigerant lines
Install drain hose with downward pitch
Secure electrical wire and conduit
Step 5: Electrical Wiring (1–2 hours)
Install disconnect box (if not present)
Wire indoor and outdoor units
Ground system properly
Connect to breaker box
Step 6: Vacuum and Charge (30–60 min)
Evacuate lines with vacuum pump
Open refrigerant valves or add charge
Pressure test for leaks
Step 7: Final Testing (30 min)
Power on and test cooling
Confirm thermostat and modes work
Inspect airflow and noise levels
Installing Multi-Zone Mini Splits
Multi-zone installs take more time due to:
Multiple indoor unit mounts
More complex wiring and refrigerant routing
Longer drain and conduit runs
Balancing refrigerant pressure across units
Average Time:
2 indoor heads = 1 day
3–5 indoor heads = 1.5 to 2 days
Electrical Work Requirements
Mini splits typically require:
Dedicated 240V circuit (for most models)
15–30 amp breaker
Outdoor disconnect box
Electrical permit in most towns/cities
If your panel lacks capacity, expect 2–4 hours extra for upgrades. Always hire a licensed electrician for high-voltage work.
Permits and Local Code Considerations
Depending on your location, you may need:
HVAC mechanical permit
Electrical permit
Final inspection post-install
In states like Massachusetts, California, and New York, strict code compliance means permit delays can extend the project. Check with your local building department.
DIY vs. Professional Installation Time
DIY Kits:
Brands like Mr. Cool and Senville offer pre-charged mini split systems that don't require vacuuming lines, making DIY installs easier.
Estimated DIY time: 6–12 hours
Risk of improper line connections, electrical hazards
Warranty may be voided without pro install
Professional Installers:
Licensed, insured, and experienced
Installation in 4–8 hours (single-zone)
Peace of mind with warranty compliance
Troubleshooting and Delays
Unexpected issues can add hours or even days:
Problem | Time Impact | Solution |
Wall is concrete or brick | +2–3 hours | Use masonry tools |
Long line set run | +1–2 hours | Use line hide kits and insulation |
Circuit panel lacks capacity | +4–6 hours | Schedule electrician upgrade |
Hidden plumbing/wires in wall | +2 hours or more | Use wall scanner to detect |
Rain or outdoor access issues | Delay of 1 day | Check weather forecast before |
Tips to Speed Up the Installation
✅ Pre-mark unit locations
✅ Have a level, pre-installed pad for condenser
✅ Run conduit paths early
✅ Choose a unit with a pre-charged line set
✅ Clear room access before the team arrives
✅ Ensure electrical access is ready
FAQ
❓ Can a mini split be installed in one day?
Yes! A single-zone mini split typically takes 4–8 hours with a professional crew.
❓ Is a permit required for installation?
Often yes. Most states require a mechanical permit, and sometimes an electrical permit too.
❓ Can I install it myself?
If it’s a DIY-rated model (like Mr. Cool), yes—but professional installation is safer and may be required for the warranty.
❓ How many technicians are needed?
A team of 2–3 can install most systems efficiently in a day.
❓ How long does it take to install a mini split in an attic or basement?
Expect 8–12 hours due to limited access and longer line runs.
Final Thoughts
Mini split systems offer unmatched flexibility, energy efficiency, and comfort—but proper installation is essential. For most standard setups, a professional can complete a single-zone install in just one day. Complex systems or additional zones may require 1.5 to 2 days, especially if electrical work or structural challenges are involved.
Before you install:
Know your system’s requirements
Prepare your space ahead of time
Work with a licensed contractor or qualified electrician
Understand local permitting needs
With the right prep and professional help, you’ll be enjoying quiet, efficient cooling in no time.
Need a quote or advice on your mini split install?Reach out to a licensed HVAC pro in your area and schedule a consultation today.
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