This is the outdoor condenser unit only, model 37MGRAQ18CA3, for a Carrier Performance 25 multi-zone ductless heat pump system. It's built for homeowners who want to run up to several indoor zones β bedrooms, additions, converted spaces β off one outdoor unit, without ductwork. Indoor heads, line sets, and mounting accessories are sold separately.
The 37MGRAQ18CA3 is the outdoor half of a Carrier Performance 25 multi-zone ductless heat pump system, built to pair with up to six AHRI-matched indoor heads (sold separately) drawn from Carrier's compatible 37MGRA-series lineup. It carries an ENERGY STAR certification and is rated up to 25.2 SEER2 / 9.8 HSPF2 in AHRI-matched system configurations. This unit uses R-454B (Puron Advance) refrigerant, an A2L mildly flammable classification requiring licensed HVAC installation. 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 25 multi-zone heat pump, model 37MGRAQ18CA3, size 18K, variable-speed inverter compressor
- Indoor unit(s): NOT included with this listing β select compatible wall-mounted, cassette, ducted, or floor/ceiling indoor heads separately, sized to a combined capacity matched to this outdoor unit
Installation Requirements & Accessories
- Voltage: 208/230V, single-phase power supply
- Minimum Circuit Ampacity (MCA): 16A; Maximum Overcurrent Protection (MOPA): 20A
- Liquid pipe connection: 3x1/4in; Suction pipe connection: 3x3/8in
- Standard piping length: 24.6 ft (7.5m); Total maximum piping length across all zones: 196.9 ft (60m)
- Line set is sold separately β not included with this outdoor unit
- Indoor unit(s), wall sleeve, and mounting bracket are NOT included and must be purchased separately
- Professional installation required β this is not a DIY/pre-charged quick-connect system
- Not compatible with 115V-only circuits
- Not a listed match for indoor units outside the AHRI-certified 37MGRA-compatible indoor lineup
Pro-Installer Tip
R-454B is an A2L mildly flammable refrigerant, so flare connections at both the outdoor unit and every indoor head need to be leak-free from day one β a loose or under-torqued flare here is the most common cause of a slow refrigerant leak that shows up months later as reduced capacity or a communication/pressure fault. Torque every flare joint to the fitting manufacturer's spec using a digital torque wrench rather than "feel," and confirm with a nitrogen pressure test before pulling vacuum. Because this is a multi-zone system feeding up to six indoor heads off shared piping, evacuation and charge verification should be performed and documented by a technician holding an EPA Section 608 certification, consistent with the refrigerant handling requirements for R-454B systems.
Key Benefits
- Variable-speed inverter compressor delivers steady temperature control instead of on/off cycling
- Up to 25.2 SEER2 cooling efficiency and 9.8 HSPF2 heating efficiency (Region IV) in matched system configurations
- Outdoor sound pressure level as low as 59.5 dB(A)
- Rated heating operation down to -13Β°F outdoor ambient temperature
- Supports up to six indoor zones from a single outdoor condenser
- Uses Puron Advance (R-454B) refrigerant with lower global warming potential than legacy refrigerants
Technical Table
| Spec | Value | Unit |
|---|---|---|
| Cooling Capacity (Rated) | 18000 | BTU/h |
| SEER2 | 25.2 | SEER2 |
| EER2 | 14 | EER2 |
| HSPF2 (Region IV) | 9.8 | HSPF2 |
| HSPF2 (Region V) | 7.8 | HSPF2 |
| Voltage | 208/230 | V |
| Minimum Circuit Ampacity (MCA) | 16 | A |
| Max Overcurrent Protection (MOPA) | 20 | A |
| Outdoor Sound Pressure Level | 59.5 | dB(A) |
| Operating Range | -13 to 75 | Β°F |
| Net Weight | 100.53 | lbs |
| Liquid Pipe Connections | 3x1/4 | in |
| Suction Pipe Connections | 3x3/8 | in |
| Standard Piping Length | 24.6 (7.5) | ft (m) |
| Total Maximum Piping Length | 196.9 (60) | ft (m) |
| Max Zones Supported | 6 | zones |
| Refrigerant Type | R-454B (Puron Advance) | β |
Note: See "Resources (System Manuals and Warranty)" Tab above for full specifications.
Compatibility & Fitment
- Compatible with dedicated 208/230V single-phase circuits only
- Designed to pair with up to six AHRI-certified indoor units from Carrier's compatible 37MGRA-series indoor lineup
- Not compatible with 115V-only electrical circuits
- Not a listed match for indoor units outside the AHRI-certified compatible lineup for this outdoor family
- Line set is NOT included β must be purchased separately, sized per the liquid/suction pipe connections listed above
- Indoor unit(s), wall sleeve, and mounting bracket are NOT included with this outdoor-unit listing
FAQ
What breaker size do I need for this system?
The 37MGRAQ18CA3 outdoor unit has a Minimum Circuit Ampacity (MCA) of 16A and a Maximum Overcurrent Protection (MOPA) rating of 20A on a 208/230V circuit. A licensed electrician should size the breaker and wiring to local code based on 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 system uses R-454B refrigerant (an A2L mildly flammable classification) and requires professional installation by a licensed HVAC technician, including proper vacuum evacuation and refrigerant handling under EPA Section 608.
Is the line set included, and if not, what size do I need to buy?
Line sets are sold separately. For the 18K outdoor connection point, liquid pipe is 1/4in and suction pipe is 3/8in per zone connection. Standard piping length is 24.6 ft (7.5m), with a total maximum system piping length of 196.9 ft (60m) across all zones.
Does this system work in cold climates (low-ambient heating)?
Yes. The published operating range for the 37MGRAQ18CA3 outdoor unit is -13Β°F to 75Β°F, which supports heating operation in low-ambient winter conditions.
How many indoor zones can this outdoor unit support?
The 37MGRA family outdoor units support up to six compatible indoor units per system, depending on outdoor unit size and total combined indoor capacity. Indoor units are sold separately and must be AHRI-matched.
Compliance & Warranty
Installation by a licensed HVAC professional is required to maintain warranty. This system uses R-454B refrigerant, requiring handling by a technician holding EPA Section 608 certification. Carrier's Consumer Choice Warranty applies upon timely registration: on eligible equipment, you can select either a 10-year parts-only limited warranty or a 5-year parts plus 3-year labor limited warranty. Refer to the manufacturer warranty documentation in the "Resources (System Manuals and Warranty)" Tab above for exact terms and registration requirements.
