Ductless Mini-Split Installation & Repair in Oklahoma
4.8 STARS / 276 REVIEWS · KINGFISHER + OKC METRO · SAME-DAY AVAILABLE
Hartzell’s Heat & Air is one of only a handful of Mitsubishi Diamond Dealers in Oklahoma, and Dave Hartzell has been installing and servicing ductless mini-splits long enough to know what separates a good installation from a callback. The difference usually comes down to three things: correct load calculation instead of a rule-of-thumb guess, proper line-set routing that protects the refrigerant from UV and physical damage, and warranty registration completed at startup, which is what activates Mitsubishi’s exclusive 12-year Diamond Dealer coverage. Standard dealers offer 5 years. Hartzell’s offers 12, at no extra cost.
Don’t wait until it’s an emergency. Same-day and next-day slots fill fast during peak season. Call 405-375-4822 to check availability, or use the chat button in the corner.
Mini-split installation starts at $1,999 installed for a single-zone system. Multi-zone systems range from $4,500 to $13,000 installed depending on the number of zones and equipment tier. Free estimates on all installations.
Ductless mini-splits deliver efficient, zoned comfort without new ductwork, ideal for additions, shops, and whole-home upgrades. Hartzell’s is a Mitsubishi Diamond Dealer serving Kingfisher County and central Oklahoma. Call 405-375-4822 for a free estimate.
✓ Mitsubishi Diamond Dealer
✓ 12-Year Warranty
✓ Kingfisher for 15+ years
Highest Mitsubishi Contractor Certification
◆ Mitsubishi Diamond Dealer
One of only a handful of Diamond-certified contractors in all of Oklahoma. Factory trained. Factory accountable on every install. There is exactly one thing only Diamond Dealers can give you:
Standard dealer
5 yrs
Hartzell’s Diamond
12 yrs
12-year parts and labor warranty. Registered at startup. No extra cost.
Trane Unstoppable Event, Ends June 30, 2026
0% Financing for 60 Months
+ Up to $900 Back
Up to $900 Rebate
Price Today, Install Tomorrow
Stack with Oklahoma utility rebates for maximum savings. Call 405-375-4822
Mitsubishi Diamond Dealer, upfront pricing, same-day estimates

Which Mitsubishi System Is Right for You?
Not sure which indoor unit type fits your space? Pick the description that matches your situation and I’ll walk you through everything on that page.
🏠
Wall Mount
One room: garage, bedroom, sunroom, office, bonus room. Most popular option. Starts at $1,999.
See wall mount options →
⬇
Ceiling Cassette
Open floor plan or commercial space. Flush in ceiling, 4-way airflow, nearly invisible. Starts at $2,800.
See ceiling cassette options →
🪟
Floor Mount
Floor-to-ceiling windows, cathedral ceilings, sunrooms, mobile homes. Starts at $2,200.
See floor mount options →
What Is a Ductless Mini-Split System?
A ductless mini-split is a heating and cooling system that delivers conditioned air directly to a room or zone, without any ductwork. An outdoor compressor connects to one or more indoor wall-mounted units via a small refrigerant line. Each zone can be controlled independently, which means you heat or cool exactly where you need it, and nothing else. The wall-mounted head is the most common indoor unit I install in Oklahoma. For full sizing, install costs, and which models I carry, see my Mitsubishi wall-mount mini-split details.
- No ductwork required, ideal for additions, older homes, and spaces without existing ducts
- Zoned control, set different temperatures in different rooms
- High efficiency, Mitsubishi systems reach up to 40 SEER2 ratings
- Quiet operation, indoor units run as low as 19 dB
- Year-round comfort, heat and cool with a single system
- Works in extreme temps, Mitsubishi Hyper Heat units operate down to -13°F

Ideal Applications
- Room additions where extending ductwork is impractical
- Garage conversions and workshops
- Bonus rooms, sunrooms, and finished basements
- Older homes without existing ductwork
- Home offices requiring independent climate control
- Multi-family and light commercial spaces
- Oil field offices and crew quarters
- Server rooms and equipment spaces
Ductless Mini-Split Repair
As a factory-trained Diamond Dealer, I diagnose and repair all Mitsubishi ductless systems, and service other major mini-split brands as well. Common issues I resolve:
- Unit not cooling or not heating
- Error codes on indoor unit display
- Ice or frost buildup on indoor or outdoor unit
- Water dripping from indoor head unit
- Unusual noise, clicking, rattling, or grinding
- Remote or thermostat not responding
- Weak airflow or uneven temperatures between zones
- Unit running constantly without reaching setpoint
- Refrigerant leak diagnosis and repair
Mitsubishi systems have self-diagnostic capability, error codes displayed on the unit give me a head start on diagnosis before I even open the system.
What to Expect with Installation
- Consultation & system design, I size the equipment to your actual space using load calculations, not rules of thumb. Single-zone or multi-zone configuration determined. For older homes where the wall space is taken by windows or trim, see my Mitsubishi floor-mount mini-split page.
- Installation day, Outdoor unit placed, refrigerant lines run through a small wall penetration, indoor head unit(s) mounted. Most single-zone installs complete in one day.
- Startup & registration, System commissioned, tested, and registered with Mitsubishi to activate the 12-year Diamond Dealer warranty.
Ductless Maintenance
Mini-split systems require annual maintenance to stay efficient. The indoor head unit’s washable filters need periodic cleaning, the outdoor coil should be inspected, and refrigerant levels and electrical components should be checked yearly. Neglected systems lose efficiency, develop drainage issues, and can fail prematurely.
I offer a Mini-Split Enhanced Cleaning add-on through our maintenance program, a deep clean of the indoor head unit including coil, blower wheel, and drain pan.


Check Current Mitsubishi Rebates
Mitsubishi’s Rebate Finder tool shows current manufacturer rebates by zip code, stack these with Oklahoma utility rebates for your best installed price. Call 405-375-4822 for a free quote.
Related Reading
Mini-Split Installation by a Mitsubishi Diamond Dealer
Free estimates on all mini-split installations. Single-zone, multi-zone, and ducted cassette. NATE-certified, 4.8 stars/276 reviews.
Nearby Communities I Serve
✓ $111 diagnostic fee, credited toward your repair if you accept an estimate within 14 days.
Mini-split service in Yukon, Edmond, Mustang, El Reno, Enid, Guthrie, Weatherford, and surrounding towns, same crew, same quality.
Mitsubishi Electric, Brand Videos
As a Mitsubishi Electric Diamond Dealer, Hartzell’s carries the full Mitsubishi product line, from single-zone wall units to multi-zone systems. These short videos explain what sets Mitsubishi apart. If you want a flush, low-profile install above the ceiling, see my Mitsubishi ceiling cassette options.
4 Reasons to Choose Mitsubishi Electric Heat Pumps
Mitsubishi Electric, Be Proactive
Mitsubishi Electric, Something Special
Frequently Asked Questions
Where do ductless systems make the most sense?
Great fits include sunrooms, upstairs bedrooms, shops, mother-in-law suites, and areas the main system can’t reach well.
Are they efficient in summer and winter?
Modern inverter models modulate to the load. With proper sizing and line set work, they perform well across seasons.
How loud are the indoor heads?
Most run quietly on low to medium fan speeds. I help set fan and vane modes for comfort without drafts.
Can I control multiple rooms separately?
Yes. Multi-zone systems let each room run its own temperature and schedule. For full configuration details and install costs, see my Mitsubishi multi-zone system pricing page.
Do they need special maintenance?
Keep the filters clean and schedule coil cleanings. I also check drain lines, charges, and communication cables annually.
Content reviewed by Dave Hartzell, Oklahoma Master HVAC License #00115936, IGSHPA Accredited Geothermal Installer, Mitsubishi Diamond Dealer, Trane Comfort Specialist TCS SELECT. Hartzell’s Heat & Air, Kingfisher OK, for 15+ years.
-406
Choose Your Mitsubishi System Type
Different rooms call for different head units. Here is what I install across Central Oklahoma, and when each one is the right call.
- Mitsubishi wall-mount mini-split, the most common setup, mounts high on an exterior wall.
- Mitsubishi ceiling cassette system, recessed in a drop ceiling, four-way airflow, great for open offices and large rooms.
- Mitsubishi floor-mount mini-split, sits low on the wall, perfect for sunrooms, basements, and bedrooms with high windows.
- Mitsubishi multi-zone mini-split setup, one outdoor unit feeding up to eight indoor heads with independent control.
- Mitsubishi mini-split energy savings in Oklahoma, real power-bill numbers from jobs I have installed locally.
Ready to Schedule Service?
Master HVAC tech. Upfront pricing. 4.8 stars / 276 reviews. Free estimates on new installs.