This is the outdoor condenser (outdoor unit only) for a Carrier Performance 26 single-zone ductless mini split heat pump system. It's built for homeowners and installers who already have a matched indoor head selected — this listing does not include an indoor unit, line set, or mounting accessories.
The 37MARAQ18AA3 is the size-18 (18,000 BTU/h) outdoor condensing unit in Carrier's Performance 26 single-zone lineup, rated up to 26 SEER2 and 13.9 HSPF2 in AHRI-matched system combinations. It uses a variable-speed inverter-driven compressor and Puron Advance (R-454B) refrigerant. Note: If you would like to review the manufacturer Product Specifications, Warranty, Brochure, etc., for this system, please refer to the "Resources (System Manuals and Warranty)" Tab above on this page.
System Components
- Outdoor condenser: Carrier Performance 26, model 37MARAQ18AA3, size 18K (18,000 BTU/h cooling)
- Indoor unit: NOT included — must be selected separately from an AHRI-matched indoor model (e.g., 615AHAQ18XA3, or a matched 45MCCA/45MBCA/45MBFA/45MCFA/45MBDA/45MBAA family unit rated for size 18)
Installation Requirements & Accessories
- Voltage: 208/230V; 1Ph; 60Hz
- Minimum Circuit Ampacity (MCA): 18A; Maximum Overcurrent Protection (MOCP): 20A
- Refrigerant: R-454B (Puron Advance), 3 lb (1.36 kg) charge amount for this size
- Line set piping sizes: liquid 1/4 in (6.35mm), suction 1/2 in (12.7mm)
- Line Set Sold Separately — not included with this outdoor unit
- Indoor unit, wall sleeve, and mounting bracket NOT included
- Not compatible with 115V-only circuits
- Not a listed match for indoor units outside the AHRI-certified combination table for 37MARAQ18AA3
- Professional installation required — R-454B is a mildly flammable (A2L) refrigerant requiring EPA Section 608-certified handling
Pro-Installer Tip
Flare connections on R-454B systems are unforgiving of shortcuts. A loose or over-torqued flare nut on the 1/4 in liquid line or 1/2 in suction line is the leading cause of slow refrigerant leaks that show up months later as reduced capacity or nuisance fault codes. Torque every flare joint to the connection manufacturer's spec with a calibrated digital torque wrench rather than "feel," and pull the system down to the manufacturer-specified vacuum before charging. This isn't optional paperwork — it's what keeps an A2L refrigerant system operating at its rated efficiency and in compliance with EPA Section 608 handling requirements for licensed technicians.
Key Benefits
- Variable-speed inverter compressor for smoother, more precise temperature control than fixed-speed systems
- Outdoor sound level as low as 58 dBA at this size
- Puron Advance (R-454B) refrigerant — lower global warming potential than legacy refrigerants, non-ozone-depleting
- Rated for cooling operation down to -13°F and up to 122°F ambient
- Rated for heating operation down to -13°F ambient for cold-climate applications
- Up to 26 SEER2 and 13.9 HSPF2 in AHRI-matched system configurations
| Spec | Value | Unit |
|---|---|---|
| Cooling Rated Capacity | 18000 | Btu/h |
| SEER2 (system, matched indoor) | Up to 26 | — |
| HSPF2 (system, matched indoor) | Up to 13.9 | — |
| Voltage | 208/230;1Ph;60Hz | V |
| Minimum Circuit Ampacity (MCA) | 18 | A |
| Maximum Overcurrent Protection (MOCP) | 20 | A |
| Outdoor Sound Level | 58 | dBA |
| Refrigerant Type | R-454B | — |
| Refrigerant Charge Amount | 3 (1.36) | lb (kg) |
| Liquid Pipe Size | 1/4 (6.35) | in (mm) |
| Suction Pipe Size | 1/2 (12.7) | in (mm) |
| Net Weight | 92.59 | lb |
| Gross Weight | 100.31 | lb |
| Cooling Operating Range | -13 to 122 (-25 to 50) | °F (°C) |
| Heating Operating Range | -13 to 75 (-25 to 24) | °F (°C) |
| Compressor Type | Variable-speed inverter | — |
| Zone Count | 1 (single-zone) | — |
Note: See "Resources (System Manuals and Warranty)" Tab above for full specifications.
Compatibility & Fitment
- Compatible with dedicated 208/230V single-phase circuits sized to 18A MCA / 20A MOCP
- Matched to AHRI-certified indoor units in the 37MARAQ18AA3 combination table (size 18 family), including options across wall-mount, 4-way cassette, 1-way cassette, slim duct, and floor console architectures per manufacturer documentation
- Not compatible with 115V-only circuits
- Not a listed match for indoor models outside the size-18 AHRI-matched combination table
- Line set NOT included — this is not a pre-charged DIY kit
- Wall sleeve and mounting bracket NOT included
FAQ
What breaker size do I need for this system?
The 37MARAQ18AA3 outdoor unit has a Minimum Circuit Ampacity (MCA) of 18A and a Maximum Overcurrent Protection (MOCP) of 20A. A licensed electrician should size the dedicated circuit and breaker per the National Electrical Code and local codes using these values.
Is professional installation required to keep the warranty valid, or is this a true DIY kit?
This is not a DIY kit. This outdoor unit uses R-454B (A2L) refrigerant and requires professional installation by a licensed HVAC technician. Installation by a licensed professional is required to maintain warranty coverage.
Is the line set included, and if not, what size do I need to buy?
The line set is sold separately. For the 37MARAQ18AA3 (size 18), the liquid line is 1/4 in (6.35mm) and the suction line is 1/2 in (12.7mm).
Does this system work in cold climates (low-ambient heating)?
Per manufacturer data, the heating operating range for this outdoor unit is -13°F to 75°F (-25°C to 24°C), and the cooling operating range is -13°F to 122°F (-25°C to 50°C).
What indoor unit does this outdoor unit come with?
This listing is the outdoor condenser only. No indoor unit is included. The indoor head, matched by AHRI certification to the 37MARAQ18AA3 outdoor unit, must be purchased separately.
Compliance & Warranty
Installation by a licensed HVAC professional is required to maintain warranty. This system uses R-454B (A2L) mildly flammable refrigerant and must be installed and serviced only by EPA Section 608-certified technicians. Under Carrier's Consumer Choice Warranty, upon timely registration on eligible equipment, you can choose either a 10-year parts-only limited warranty or a 5-year parts plus 3-year labor limited warranty. See the manufacturer warranty documentation in the Resources tab for full terms and registration requirements.
