Della / Optima Pro Series
Della Optima Pro 9k R-454B 208/230V Mini-Split
The Optima Pro 9k is a flagship small-room unit that actually gains heating capacity as the temperature drops. It rates a category-leading SEER2 25, EER2 14.5, and HSPF2 10.5, heating 9,000 BTU/h at 47F, rising to 10,000 BTU/h at 17F, and holding 9,100 BTU/h at 5F. It is a top pick for a small space in a cold climate.
Refrigerant generation
R-454B - current-generation refrigerant
Paid link
$1,050 / Fresh price - checked Jul 24, 2026
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Image: Della
- Last sourced
- Jul 24, 2026
SplitAtlas score
8.4 / 10
(25.0 SEER2) among <=9k systems
(10.5 HSPF2) among <=9k systems
(100% heat retained at 5F; -22 F heating floor) among <=9k systems
(26 dBA indoor min / 55 dBA outdoor) among <=9k systems
(DIY-marketed; 25 ft precharged; 16.4 ft included line set) across the catalogue
(5 verified features) across the catalogue
($1,050 median retail) among <=9k systems
(3 manuals; spec sheet) across the catalogue
Key ratings
Buyer review snapshot
Best for / skip if
Best for
- Top efficiency shortlists; SEER2 is 25.
Install difficulty
- Electrical: 230V; breaker/fuse 15 A.
- Line set: Flared line connections; precharged 25 ft; included 16.4 ft; max 49 ft.
Alternatives
- Blueridge XS6 Max Efficiency 9,000 BTU R-454B 208/230V (BXS6A09WM0 / BXS6A09UC0)
8.9 score / 9k / SEER2 33.3 / -22 F heating floor / 230V
Exact destination at Alpine Home Air: $1,689.00, checked Jul 24, 2026
- Senville ELITE 9,000 BTU R-454B 208/230V (SENE-09EL-IHH / SENE-09EL-OH)
8.8 score / 9k / SEER2 33.3 / -22 F heating floor / 187-253V
Exact destination at Senville: $1,599.99, checked Jul 24, 2026
- ACiQ Extreme 9,000 BTU R-454B 208/230V (ACIQ-09W-HH-MD / ACIQ-09ZPL-HP230C)
8.8 score / 9k / SEER2 27.4 / -22 F heating floor / 230V
Exact destination at HVACDirect: $1,499.99, checked Jul 26, 2026
Availability and price context
- Verified current price: $1,049.96 at Della; availability out_of_stock; checked Jul 24, 2026.
Source date
- Model data sourced
- Jul 24, 2026
- Page reviewed
- Jul 24, 2026
- Source-backed records
- 4
- Newest source retrieved
- Jul 24, 2026
Warranty tiers
Warranty: Lifetime warranty claim on Della product page
Model context
- Structured ratings
- Certification: ENERGY STAR certified. Refrigerant: current low-GWP R-454B. Minimum heating ambient: -22 F.
Strengths
- Produces more heat at both 17F (10,000 BTU/h) and 5F (9,100 BTU/h) than at 47F, a genuine cold-weather gain.
- SEER2 25 and EER2 14.5 are the highest efficiency numbers in Della's line-up, and it is ENERGY STAR certified.
Weaknesses
- Della's dealer and service network is smaller than that of established premium brands.
- Professional install is recommended; DIY refrigerant handling done wrong can affect the warranty.
Climate suitability
- Minimum heating ambient
- -22 F[1]
- Rated heating at 5F
- 9,100 BTU/h[3]
- Rated heating at 17F
- 10,000 BTU/h[3]
- Rated heating at 47F
- 9,000 BTU/h[3]
Specifications
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- Manufacturer
- Della
- Brand
- Della
- Product line
- Optima Pro Series
- Model number
- 048-TPH-9K2V-25S-IN indoor / 048-TPH-9K2V-25S-OUT outdoor
- Indoor unit model
- 048-TPH-9K2V-25S-IN
- Outdoor unit model
- 048-TPH-9K2V-25S-OUT
- Number of zones
- 1
- Max indoor units
- not published
- Rated cooling capacity
- 9,000 BTU/h[3]
- Rated heating capacity
- 9,000 BTU/h[3]
- Voltage
- 230 V[1]
- MCA
- not published - manufacturer specifies 15 A breaker
- Maximum fuse or breaker size
- 15 A[1]
- Breaker needed
- 15 A[1]
- SEER2
- 25 SEER2[3]
- EER2
- 14.5 EER2[3]
- HSPF2 (Region 4)
- 10.5 HSPF2[3]
- HSPF2 (Region 5)
- not published
- COP
- not published
- COP at 47F
- not published
- COP at 5F
- 1.8 COP[3]
- Minimum outdoor heating temperature
- -22 F[1]
- Minimum outdoor cooling temperature
- not published
- Maximum outdoor temperature
- 131 F[1]
- Indoor noise range
- 26 - 42 dBA[2]
- Outdoor noise rating
- 55 dBA[2]
- Indoor weight
- 23.1 lb[1]
- Outdoor weight
- 54.013 lb[1]
- Refrigerant
- R-454B[3]
- Refrigerant charge
- not published
- Manufacturer coverage
- not published
- Line-set size
- 1/4 in liquid / 3/8 in suction
- Included line-set length
- 16.4 ft[1]
- Maximum line-set length
- 49 ft[2]
- Max line set per indoor
- not published
- Maximum elevation difference
- 33 ft[2]
- Max height between indoor units
- not published
- Wi-Fi support
- supported[1]
- Energy Star status
- ENERGY STAR certified[4]
- AHRI certification number
- 217568636[3]
- Warranty
- Lifetime warranty claim on Della product page
- Install path
- Professional install / DIY-marketed
- Marketing install label
- DIY-marketed
- Retail price
- $1,049.96
- Available retailers
- Della
- Manual links
- AHRI Appendix M1 public detail record 217568636, Optima Pro Series installation and operation guide, Optima Pro 9,000 BTU Della product-page specifications
- Specification sheet
- Optima Pro 9,000 BTU Della product-page specifications
- Last sourced date
- Jul 24, 2026
Retail purchase context
Some retailer links may earn us a commission at no extra cost; paid relationships never change scores or recommendations. Affiliate disclosure
Paid link
$1,050 / Fresh price - checked Jul 24, 2026
Electrical requirements
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- Voltage
- 230 V[1]
- Voltage range
- 208/230V[1]
- Phase
- 1[1]
- Frequency
- not published
- MCA
- not published - manufacturer specifies 15 A breaker
- Breaker needed
- 15 A[1]
- Maximum breaker size
- not published
- Maximum fuse size
- 15 A[1]
- Maximum cooling current
- not published
- Maximum heating current
- not published
- Manufacturer wire notes
- not published
Installation considerations
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- Liquid line
- 1/4 in[1]
- Suction line
- 3/8 in[1]
- Line connection type
- Flared line connections[2]
- Precharged length
- 25 ft[2]
- Included line-set length
- 16.4 ft[1]
- Maximum line-set length
- 49 ft[2]
- Max line set per indoor
- not published
- Max height between indoor units
- not published
- Indoor dimensions
- 32.25 in W x 12.06 in H x 7.69 in D[1]
- Outdoor dimensions
- 31.88 in W x 21.63 in H x 12 in D[1]
- Indoor weight
- 23.1 lb[1]
- Outdoor weight
- 54.013 lb[1]
- Drain size
- not published
Related systems and guides
- More Della systems
- Optima CloudAir Series 9k
- Della sibling model
- Della Optima CloudAir Series 9k 115V
- Della 230 V option
- Guide library
- Mini split buying guide
- Single-zone vs multi-zone mini splits
- Troubleshooting
- Do mini splits work in cold weather?
- Della mini split review: is Della any good?
- The best 9,000 BTU mini splits of 2026
- The best cold-climate mini splits of 2026
- The best mini splits for heating of 2026
- Mini split heating capacity in the cold: what your unit actually delivers at 5F
- The mini split defrost cycle, explained
- The best DIY mini splits of 2026
- What "DIY mini split" actually means
- How to install a mini split (DIY overview)
- Mini split not heating
- Mini split indoor unit freezing up
- Mini split remote not working
- Mini split condensate pump problems
- Mini split lights blinking
- Line sets
- Line-set covers
Frequently asked questions
- Can I install the Della Optima Pro 9,000 BTU R-454B 208/230V (048-TPH-9K2V-25S-IN / 048-TPH-9K2V-25S-OUT) myself, or do I need a pro?
- Della Optima Pro 9,000 BTU R-454B 208/230V (048-TPH-9K2V-25S-IN / 048-TPH-9K2V-25S-OUT) is built for professional installation: the line set must be flared, evacuated, and charged, which requires EPA-certified refrigerant handling. Installing it outside the manufacturer's requirements can void the warranty, so budget for a qualified HVAC installer.
- Will the Della Optima Pro 9,000 BTU R-454B 208/230V (048-TPH-9K2V-25S-IN / 048-TPH-9K2V-25S-OUT) keep heating in a cold winter?
- The manufacturer publishes 9,100 BTU/h of heating output at 5F. Rated heating operation extends down to -22 F. Certified heating efficiency is 10.5 HSPF2. Match those numbers against your climate's design temperature - in cold regions, output at 5F matters far more than the nameplate capacity measured at 47F.
- What electrical circuit does the Della Optima Pro 9,000 BTU R-454B 208/230V (048-TPH-9K2V-25S-IN / 048-TPH-9K2V-25S-OUT) need?
- Published electrical requirements: 230 V voltage, not published - manufacturer specifies 15 A breaker minimum circuit ampacity, and 15 A maximum breaker or fuse sizing. Confirm the final circuit against the unit nameplate and local code with a licensed electrician.
- How far can the outdoor unit be from the indoor head?
- The published maximum line-set length is 49 ft, and the included line set comes pre-charged for 25 ft. Longer runs than the included set allows typically mean added refrigerant and a pro visit, so measure the planned routing before ordering.
Data sources
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- Della: DELLA Optima Pro Series 9000 BTU 25 SEER2 Ultra Hyper Heat Mini-Split AC - Up to 400 Sq.Ft. official product pageSourced - manufacturer product page
Covers Breaker needed, Maximum fuse size, Phase, Voltage, Voltage range, Included line-set length and more
- Della: Optima Pro Series installation and operation guideSourced - manufacturer technical document
Covers Indoor noise range, Line connection type, Maximum elevation difference, Maximum line-set length, Outdoor noise rating, Precharged length
- AHRI certificate #217568636 - search the AHRI DirectorySourced - AHRI directory
Covers AHRI certification number, Rated cooling capacity, COP at 5F, EER2, Rated heating capacity, HSPF2 (Region 4) and more
- ENERGY STAR: ENERGY STAR exact row check for AHRI 215864147Sourced - Energy Star listing
Covers Energy Star status
Last updated
Jul 24, 2026