Fujitsu / AIRSTAGE H-series
Fujitsu AIRSTAGE H-series 18k Compact Cassette R-32 208/230V Mini-Split
The Fujitsu AIRSTAGE H-series Compact Cassette 18k pairs ACUH18KUAS with AOUH18KUAS1 for a professional, dealer-quoted compact ceiling cassette installation instead of a wall head. It certifies at 18,000 BTU cooling and 21,600 BTU heating at 47F, with 21.9 SEER2, 12.6 EER2, and 11.3 HSPF2. Its certified 5F output is 17,100 BTU, matching or beating the 17F rating, so it is a serious cold-weather candidate.
Refrigerant generation
R-32 - current-generation refrigerant
- Last sourced
- Aug 5, 2026
SplitAtlas score
8.9 / 10
(21.9 SEER2) among 18k systems
(11.3 HSPF2) among 18k systems
(79.2% heat retained at 5F; -5 F heating floor) among 18k systems
(-44 dBA indoor min / 55 dBA outdoor) among 18k systems
(3 manuals; spec sheet; 36 error-code rows) across the catalogue
Not evaluated
- Installation accessibility — not applicable (professional install)N/A
professional install - DIY-accessibility not applicable
- Price-to-value — not evaluatedN/A
quote-only - no retail price to evaluate
Key ratings
Best-fit use cases
Best for open rooms, offices, and ceiling-grid spaces where a centered cassette is worth the ceiling work around 650-900 sq ft, where the owner wants Fujitsu dealer support and the alternate indoor form is worth the installation work.
Buyer review snapshot
Install difficulty
- Electrical: 208/230V; MCA 14.8 A; breaker/fuse 20 A.
- Line set: connection type not sourced; precharged 66 ft; max 98 ft.
Alternatives
- Blueridge XS6 Max Efficiency 18,000 BTU R-454B 208/230V (BXS6A18WM0 / BXS6A18UC0)
9.0 score / 18k / SEER2 25.6 / -22 F heating floor / 230V
Exact destination at Alpine Home Air: $2,359.00, checked Jul 24, 2026
Availability and price context
We could not verify a current retail price for this model. We could not find this exact model in stock at a retailer we work with when we last checked on 2026-08-05.
Purchase channel policy
Fujitsu/GENERAL says online retail sales of its products are not authorized; buyers should treat public online carts as outside the approved purchase channel.
- Warranty consequence
- Warranty becomes null and void for online purchases.
- Authorized channel
- Authorized local distributor or contractor channel; password-protected distributor sites are for qualified technicians.
Any online offer for this brand should be treated as a warranty-risk warning, not a recommendation.
Compare online-purchase warranty rules by brand
Source: Fujitsu General America, Inc.: GENERAL AIRSTAGE MINI-SPLITS FAQ - online purchase policy; retrieved Aug 12, 2026.
Source date
- Model data sourced
- Aug 5, 2026
- Page reviewed
- Aug 5, 2026
- Source-backed records
- 3
- Newest source retrieved
- Aug 5, 2026
Model context
- Fujitsu dealer channel
- Fujitsu equipment here is professional-install and quote-based; online purchase restrictions are handled in the purchase-channel policy when that brand fact is sourced.
- Install path
- This is professional-install equipment; no verified current retail offer is attached. Brand purchase-channel policy is shown in the buyer review snapshot.
- Installation context
- Ceiling-mounted indoor units need a workable ceiling cavity, panel clearance, drain routing, and service access. Cold-weather output still needs a load calculation and installation clearances, not just the published AHRI rating.
Strengths
- 18,000 BTU of compact ceiling cassette capacity on current R-32 refrigerant.
- 21.9 SEER2 / 12.6 EER2 / 11.3 HSPF2 certified efficiency.
- 14,400 BTU at 17F and 17,100 BTU at 5F give real winter numbers to size against.
Weaknesses
- At 21.9 SEER2 it gives up 4.4 points to the 18k Circular-Flow Cassette in the same line, so the ceiling format is about distribution and fit rather than the H-Series efficiency peak. It also needs a 20 A circuit where the smallest cassette heads in the H-Series run on 15 A, so the electrical work is not a like-for-like swap.
Climate suitability
- Minimum heating ambient
- -5 F[1]
- Rated heating at 5F
- 17,100 BTU/h[2]
- Rated heating at 17F
- 14,400 BTU/h[2]
- Rated heating at 47F
- 21,600 BTU/h[2]
Specifications
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- Manufacturer
- Fujitsu
- Brand
- Fujitsu
- Product line
- AIRSTAGE H-series
- Model number
- ACUH18KUAS indoor / AOUH18KUAS1 outdoor
- Indoor unit model
- ACUH18KUAS
- Outdoor unit model
- AOUH18KUAS1
- Number of zones
- 1
- Max indoor units
- not published
- Rated cooling capacity
- 18,000 BTU/h[2]
- Rated heating capacity
- 21,600 BTU/h[2]
- Voltage
- 208/230V[1]
- MCA
- 14.8 A[1]
- Maximum fuse or breaker size
- 20 A[1]
- Breaker needed
- not published
- SEER2
- 21.9 SEER2[2]
- EER2
- 12.6 EER2[2]
- HSPF2 (Region 4)
- 11.3 HSPF2[2]
- HSPF2 (Region 5)
- not published
- COP
- not published
- COP at 47F
- 3.54 COP[1]
- COP at 5F
- 2.2 COP[2]
- Minimum outdoor heating temperature
- -5 F[1]
- Minimum outdoor cooling temperature
- -5 F[1]
- Maximum outdoor temperature
- 122 F[1]
- Indoor noise range
- cooling 29-42; heating 30-44 dB(A)[1]
- Outdoor noise rating
- 55 dBA[1]
- Indoor weight
- 35 lb[1]
- Outdoor weight
- 84 lb[1]
- Refrigerant
- R-32[1]
- Refrigerant charge
- 44 oz[1]
- Manufacturer coverage
- not published
- Line-set size
- 1/4 in liquid / 1/2 in suction
- Included line-set length
- Fujitsu publishes pre-charge length and flared line sizes; the installer supplies the line set.
- Maximum line-set length
- 98 ft[1]
- Max line set per indoor
- not published
- Maximum elevation difference
- 49 ft[1]
- Max height between indoor units
- not published
- Wi-Fi support
- supported[1]
- Energy Star status
- ENERGY STAR certified[2]
- AHRI certification number
- 215434547[2]
- Warranty
- not published
- Install path
- Professional install
- Retail price
- We could not find this exact model in stock at a retailer we work with when we last checked on 2026-08-05.
- Available retailers
- not published
- Manual links
- Fujitsu ACUH18KUAS installation manual, Fujitsu Connect product record AOUH18KUAS1, Fujitsu AIRSTAGE H-series Compact Cassette submittal - ACUH18KUAS / AOUH18KUAS1
- Specification sheet
- Fujitsu AIRSTAGE H-series Compact Cassette submittal - ACUH18KUAS / AOUH18KUAS1
- Last sourced date
- Aug 5, 2026
Electrical requirements
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Installation considerations
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- Liquid line
- 1/4 in[1]
- Suction line
- 1/2 in[1]
- Line connection type
- not published
- Precharged length
- 66 ft[1]
- Included line-set length
- Fujitsu publishes pre-charge length and flared line sizes; the installer supplies the line set.
- Maximum line-set length
- 98 ft[1]
- Max line set per indoor
- not published
- Max height between indoor units
- not published
- Indoor dimensions
- 9-5/8 x 22-7/16 x 22-7/16 in[1]
- Outdoor dimensions
- 24-7/8 x 31-7/16 x 11-7/16 in[1]
- Indoor weight
- 35 lb[1]
- Outdoor weight
- 84 lb[1]
- Drain size
- not published
Related systems and guides
- More Fujitsu systems
- AIRSTAGE H-series 18k
- Fujitsu 18k model
- Fujitsu 18k model
- AIRSTAGE H-series 18k
- Guide library
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- Line sets
- Line-set covers
Frequently asked questions
- Can I install the Fujitsu AIRSTAGE H-series Compact Cassette 18,000 BTU R-32 208/230V (ACUH18KUAS / AOUH18KUAS1) myself, or do I need a pro?
- Fujitsu AIRSTAGE H-series Compact Cassette 18,000 BTU R-32 208/230V (ACUH18KUAS / AOUH18KUAS1) 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 Fujitsu AIRSTAGE H-series Compact Cassette 18,000 BTU R-32 208/230V (ACUH18KUAS / AOUH18KUAS1) keep heating in a cold winter?
- The manufacturer publishes 17,100 BTU/h of heating output at 5F. Rated heating operation extends down to -5 F. Certified heating efficiency is 11.3 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 Fujitsu AIRSTAGE H-series Compact Cassette 18,000 BTU R-32 208/230V (ACUH18KUAS / AOUH18KUAS1) need?
- Published electrical requirements: 208/230V voltage, 14.8 A minimum circuit ampacity, and 20 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 98 ft, and the included line set comes pre-charged for 66 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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- Fujitsu General America, Inc.: Fujitsu AIRSTAGE H-series Compact Cassette submittalSourced - manufacturer technical document
Covers Frequency, electrical_spec.guaranteed_voltage_range, Maximum breaker size, Minimum circuit ampacity, Phase, Voltage range and more
- Air-Conditioning, Heating, and Refrigeration Institute: AHRI Active form-factor row 217895718Sourced - AHRI directory
Covers AHRI certification number, Rated cooling capacity, COP at 5F, EER2, Energy Star status, Rated heating capacity and more
- Fujitsu General America, Inc.: Fujitsu AIRSTAGE warranty pageSourced - manufacturer product page
Covers Legacy compressor warranty value, Legacy warranty value
Last updated
Aug 5, 2026