Carrier / Comfort 22
Carrier Comfort 22 18k R-454B 208/230V Mini-Split
This 18,000 BTU Comfort 22 uses R-454B on 230V and posts 20.3 SEER2, 11.5 EER2, and 9.1 HSPF2. Heating is rated 18,800 BTU at 47F, 14,000 BTU at 17F, and 11,500 BTU at 5F. It is ENERGY STAR certified but not cold-climate designated, so read its low-temperature output as decent-but-not-guaranteed for deep cold.
Refrigerant generation
R-454B - current-generation refrigerant
This brand doesn't honor its warranty on systems bought online. Buy it through a local contractor who installs it: get quotes from installers in your area, and ask whether they're an authorized dealer for this brand.
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Image: Carrier
- Last sourced
- Jul 27, 2026
SplitAtlas score
7.5 / 10
(20.3 SEER2) among 18k systems
(9.1 HSPF2) among 18k systems
(5F certified capacity: 61.2% of the 47F rating; 5 F heating floor) among 18k systems
(10 yr parts, no separate compressor term) across the catalogue
(4 verified features) across the catalogue
(6 manuals; spec sheet; 33 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
This is a professionally installed, quote-only system, so we can't score its price. Get an installed quote to compare real cost.
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Key ratings
Buyer review snapshot
Install difficulty
- Electrical: 230V.
Alternatives
- Blueridge XS6 Max Efficiency 18,000 BTU R-454B 208/230V (BXS6A18WM0 / BXS6A18UC0)
9.2 score / 18k / SEER2 25.6 / -22 F heating floor / 230V
Exact destination at Alpine Home Air: $2,359.00, checked Jul 24, 2026
- Senville ELITE 18,000 BTU R-454B 208/230V (SENE-18EL-IHH / SENE-18EL-OH)
9.0 score / 18k / SEER2 25.6 / -22 F heating floor / 187-253V
Exact destination at Senville: $1,899.99, checked Jul 24, 2026
- ACiQ Standard 18,000 BTU R-454B 208/230V (ACIQ-18WS-HP230C / ACIQ-18ZS-HP230C)
9.0 score / 18k / SEER2 24 / -13 F heating floor / 230V
Exact destination at HVACDirect: $1,299.99, checked Jul 26, 2026
Availability and price context
Carrier sells this system through authorized dealers and contractors, not online, and doesn't honor its warranty on systems bought online. Get installation quotes and ask whether the installer is an authorized Carrier dealer.
Purchase channel policy
Carrier's ductless warranty excludes products purchased over the Internet; buyers should treat public online carts as outside the warranty-covered purchase channel.
- Warranty consequence
- Warranty coverage does not apply to any product purchased over the Internet.
- Authorized channel
- Licensed HVAC technician installation with defective parts returned to the distributor through a registered servicing dealer; not an internet purchase.
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: Carrier Corporation: CAC/BDP Limited Warranty Certificate - Limited Warranty for Ductless Split Units; retrieved Aug 15, 2026.
Source date
- Model data sourced
- Jul 27, 2026
- Page reviewed
- Jul 27, 2026
- Source-backed records
- 4
- Newest source retrieved
- Sep 11, 2026
Warranty tiers
- Registered
- 10 yr parts / no separate compressor term - eligible timely registered residential installation
- Dealer alternative
- 5 yr parts / no separate compressor term - Consumer Choice dealer alternative: 5-year parts plus 3-year labor through a participating dealer
The score uses Registered. Additional published terms are shown for reference and not counted in the score.
Strengths
- ENERGY STAR certified at a useful 18,000 BTU class size, opening the door to efficiency rebates.
- Strong 47F capacity near 18,800 BTU and a reasonable 11,500 BTU at 5F for a value-tier unit.
Weaknesses
- Not cold-climate certified, so Carrier does not warrant its performance for the harshest conditions.
- SEER2 in the low 20s trails the Performance and Infinity series for long-run cooling efficiency.
Climate suitability
- Minimum heating ambient
- 5 F[4]
- Certified heating at 5F
- 11,500 BTU/h[2]
- Rated heating at 17F
- 14,000 BTU/h[2]
- Rated heating at 47F
- 18,800 BTU/h[2]
Specifications
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- Manufacturer
- Carrier
- Brand
- Carrier
- Product line
- Comfort 22
- Model number
- 45MHHAQ18XC3 indoor / 37MHRAQ18AA3 outdoor
- Indoor unit model
- 45MHHAQ18XC3
- Outdoor unit model
- 37MHRAQ18AA3
- Number of zones
- 1
- Max indoor units
- not published
- Rated cooling capacity
- 18,000 BTU/h[2]
- Rated heating capacity
- 18,800 BTU/h[2]
- Voltage
- 230 V[1]
- MCA
- Not published for this model
- Maximum fuse or breaker size
- Not published for this model
- Breaker needed
- not published
- SEER2
- 20.3 SEER2[2]
- EER2
- 11.5 EER2[2]
- HSPF2 (Region 4)
- 9.1 HSPF2[2]
- HSPF2 (Region 5)
- not published
- COP
- not published
- COP at 47F
- not published
- COP at 5F
- 2 COP[2]
- Minimum outdoor heating temperature
- 5 F[4]
- Minimum outdoor cooling temperature
- 5 F[4]
- Maximum outdoor temperature
- 122 F[4]
- Indoor noise range
- Not published for this model
- Outdoor noise rating
- Not published for this model
- Indoor weight
- Not published for this model
- Outdoor weight
- Not published for this model
- Refrigerant
- R-454B[2]
- Refrigerant charge
- not published
- Manufacturer coverage
- not published
- Line-set size
- Not published for this model liquid / Not published for this model suction
- Included line-set length
- Professional installations use separately selected line sets
- Maximum line-set length
- Not published for this model
- Max line set per indoor
- not published
- Maximum elevation difference
- Not published for this model
- Max height between indoor units
- not published
- Wi-Fi support
- Not published for this model
- Energy Star status
- ENERGY STAR certified[3]
- AHRI certification number
- 215413175[2]
- Warranty
- Registered: 10 yr parts / no separate compressor term (eligible timely registered residential installation); Dealer alternative: 5 yr parts / no separate compressor term (Consumer Choice dealer alternative: 5-year parts plus 3-year labor through a participating dealer). Score uses Registered. Additional published terms are shown for reference and not counted in the score.. Consumer Choice Warranty: 10-year parts-only or 5-year parts plus 3-year labor for eligible timely registered residential installations; terms and participating dealer requirements apply.
- Install path
- Professional install
- Retail price
- Authorized dealers only
- Available retailers
- not published
- Manual links
- AHRI public directory record 215413175, ENERGY STAR exact check 215413175, Comfort 22 installation documentation locator, Carrier Comfort 22 Mini Split Heat Pump, AHRI Appendix M1 public detail 215413175
- Specification sheet
- AHRI Appendix M1 public detail 215413175
- Last sourced date
- Jul 27, 2026
Electrical requirements
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- Voltage
- 230 V[1]
- Voltage range
- 208/230V[1]
- Phase
- 1[1]
- Frequency
- 60 Hz[1]
- MCA
- Not published for this model
- Breaker needed
- not published
- Maximum breaker size
- Not published for this model
- Maximum fuse size
- Not published for this model
- Maximum cooling current
- not published
- Maximum heating current
- not published
- Manufacturer wire notes
- not published
Installation considerations
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- Liquid line
- Not published for this model
- Suction line
- Not published for this model
- Line connection type
- not published
- Precharged length
- not published
- Included line-set length
- Professional installations use separately selected line sets
- Maximum line-set length
- Not published for this model
- Max line set per indoor
- not published
- Max height between indoor units
- not published
- Indoor dimensions
- Not published for this model
- Outdoor dimensions
- Not published for this model
- Indoor weight
- Not published for this model
- Outdoor weight
- Not published for this model
- Drain size
- not published
Related systems and guides
- More Carrier systems
- Bosch Climate 5000 G4 18k Regular R-454B Mini-Split
- Carrier Infinity 27 18k R-454B 208/230V Mini-Split
- Carrier Performance Legacy 12k B/B R-410A 115V Mini-Split
Previous generation
- Bosch Climate 5000 G4 18k Max R-454B Mini-Split
- Guide library
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- Line sets
- Line-set covers
Frequently asked questions
- Can I install the Carrier Comfort 22 18,000 BTU R-454B 208/230V (45MHHAQ18XC3 / 37MHRAQ18AA3) myself, or do I need a pro?
- Carrier Comfort 22 18,000 BTU R-454B 208/230V (45MHHAQ18XC3 / 37MHRAQ18AA3) 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 Carrier Comfort 22 18,000 BTU R-454B 208/230V (45MHHAQ18XC3 / 37MHRAQ18AA3) keep heating in a cold winter?
- The AHRI/ENERGY STAR certification lists 11,500 BTU/h of heating capacity at 5F. Certified heating efficiency is 9.1 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 Carrier Comfort 22 18,000 BTU R-454B 208/230V (45MHHAQ18XC3 / 37MHRAQ18AA3) need?
- Published electrical requirements: 230 V voltage. Confirm the final circuit against the unit nameplate and local code with a licensed electrician.
- What warranty does the Carrier Comfort 22 18,000 BTU R-454B 208/230V (45MHHAQ18XC3 / 37MHRAQ18AA3) carry?
- The manufacturer publishes these warranty tiers: Registered: 10 yr parts / no separate compressor term (eligible timely registered residential installation); Dealer alternative: 5 yr parts / no separate compressor term (Consumer Choice dealer alternative: 5-year parts plus 3-year labor through a participating dealer). Score uses Registered. Additional published terms are shown for reference and not counted in the score.. Registration requirements and proof of qualified installation commonly affect coverage, so read the warranty terms before install day.
Data sources
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- Carrier Corporation: Carrier Comfort 22 Mini Split Heat PumpSourced - manufacturer product page
Covers Frequency, Phase, Voltage, Voltage range, Additional compressor warranty status, Additional published warranty conditions and more
- Air-Conditioning, Heating, and Refrigeration Institute: AHRI Appendix M1 public detail for 37MHRAQ18AA3 / 45MHHAQ18XC3Sourced - AHRI directory
Covers AHRI certification number, performance_spec.cold_climate_designation, Rated cooling capacity, COP at 5F, EER2, Rated heating capacity and more
- ENERGY STAR: ENERGY STAR exact row check for AHRI 215413175Sourced - Energy Star listing
Covers Energy Star status
- Carrier Corporation: 37MHRAQ Product Data (37MHRAQ-01PD)Sourced - manufacturer technical document
Covers Minimum outdoor cooling temperature, Minimum outdoor heating temperature, Maximum outdoor temperature
Last updated
Jul 27, 2026