This is a Carrier indoor ceiling cassette unit — the 45MCCAQ06XA3 — for use in a single- or multi-zone ductless mini split system. It's for homeowners or contractors who want a low-profile, recessed indoor head that disappears into a standard ceiling grid instead of mounting a unit on the wall. This listing is for the indoor unit only; the outdoor condenser, line set, grille, and mounting sleeve are sold separately.
The 45MCCAQ06XA3 is a slim, one-way ceiling cassette designed to install between standard 16-inch on-center joists — a distinct architecture from bulkier 4-way cassettes that require a full drop-ceiling grid. Carrier's documentation notes ENERGY STAR® certified performance is available on select size/outdoor pairings, and this indoor unit is compatible with both single- and multi-zone Carrier outdoor systems. 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
- Indoor unit (this listing): Carrier 45MCCAQ06XA3 — slim one-way ceiling cassette, 06K size
- Outdoor condensing unit: sold separately; must be a Carrier-matched, AHRI-certified pairing
- Decorative grille panel: sold separately, required to trim out the ceiling opening
- Mounting/ceiling sleeve: sold separately, required for installation
Installation Requirements & Accessories
- Voltage: 208/230V; 1Ph; 60Hz (per manufacturer power supply table)
- Refrigerant: R-454B (Puron Advance™), A2L classification — requires EPA Section 608-certified handling
- Liquid line size (06K): 1/4 in (6.35mm)
- Suction line size (06K): 3/8 in (9.52mm)
- Line set sold separately — not included with this indoor unit
- Professional installation required; this is not a pre-charged DIY quick-connect system
- Not included: outdoor condenser, grille/decorative panel, ceiling mounting sleeve
- Not compatible with 115V-only circuits
- Not a listed match for outdoor units outside Carrier's AHRI-certified 45MCCA pairings — confirm matched combination before ordering
Pro-Installer Tip
Flare connections on ceiling cassette line sets are a common callback point — a connection that's under-torqued or over-torqued leaks refrigerant slowly, and on an R-454B (A2L) system that means a service call and a compressor working outside its designed charge. Use a digital torque wrench set to the fitting manufacturer's spec, not "hand-tight plus a quarter turn," and pull the system down below the target vacuum on a calibrated micron gauge before opening the valves — a rushed evacuation is the single biggest driver of early compressor failure and "no cool" callbacks on cassette installs. Anyone touching this A2L refrigerant charge needs current EPA Section 608 certification; that's not optional paperwork, it's the legal minimum for handling R-454B.
Key Benefits
- Slim recessed profile fits standard 16-inch on-center joist bays — no significant ceiling remodel needed
- Sound level as low as 23.5 dBA at this size, per Carrier's published data
- Follow Me function with temperature-sensing remote and four fan speeds for more even room temperatures
- Compatible with single- and multi-zone Carrier outdoor systems for flexible whole-home layouts
- Puron Advance™ (R-454B) refrigerant, rated by Carrier at 75% lower global warming potential than legacy refrigerants
- Consumer Choice Warranty available on eligible equipment with timely registration
Technical Table
| Spec | Value | Unit |
|---|---|---|
| Cooling Rated Capacity (DOE A2 - 95°F) | 6500 | Btu/h |
| Cooling Rated Capacity (DOE B2 - 82°F) | 6800 | Btu/h |
| Heating Rated Capacity (DOE H12 - 47°F) | 7400 | Btu/h |
| Heating Rated Capacity (DOE H32 - 17°F) | 7000 | Btu/h |
| Heating Rated Capacity (ODE H42 - 5°F) | 8100 | Btu/h |
| SEER2 / HSPF2 / EER2 | Dependent on paired outdoor unit | — |
| Power Supply | 208/230; 1Ph; 60 | V;Ph;Hz |
| Sound Level | 23.5 | dBA |
| Refrigerant Type | R-454B (Puron Advance) | — |
| Liquid Line Size | 1/4 (6.35) | in (mm) |
| Suction Line Size | 3/8 (9.52) | in (mm) |
| Indoor Unit Architecture | Slim One-Way Ceiling Cassette | — |
| DIY Status | No — Professional Installation Required | — |
Note: See "Resources (System Manuals and Warranty)" Tab above for full specifications.
Compatibility & Fitment
- Fits standard 16-inch on-center joist bays — designed for recessed ceiling installation
- Compatible with Carrier single- and multi-zone outdoor systems using matched, AHRI-certified 45MCCA pairings
- Runs on 208/230V; 1Ph; 60Hz power supply
- Not compatible with 115V-only circuits
- Not a listed match for outdoor units outside Carrier's certified 45MCCA family pairings
- Line set, grille panel, and mounting sleeve are NOT included — sold separately
FAQ
What breaker size do I need for this system?
Breaker sizing is determined by the paired outdoor unit, not the indoor cassette alone. [NEEDS VERIFICATION] for this exact indoor/outdoor pairing — check the matched outdoor unit's nameplate data.
Is professional installation required to keep the warranty valid, or is this a true DIY kit?
This is not a DIY kit. It uses R-454B refrigerant (A2L classification) and requires professional installation by a licensed HVAC technician to maintain the manufacturer warranty.
Is the line set included, and if not, what size do I need to buy?
The line set is sold separately. For the 06K size, the manufacturer data lists a 1/4 inch (6.35mm) liquid line and a 3/8 inch (9.52mm) suction line.
Will the ceiling cassette fit between standard 16-inch on-center joists?
Yes. Carrier's manufacturer data describes this cassette's slim, compact design as fitting neatly between 16-inch joists without significant remodeling.
Does this system work in cold climates (low-ambient heating)?
Low-ambient heating performance depends on the paired outdoor unit. The manufacturer's family documentation lists an outdoor operating range down to -22°F for some outdoor models, but the specific low-temperature rating for your chosen outdoor pairing should be confirmed in the manufacturer resources for that unit.
Compliance & Warranty
Installation by a licensed HVAC professional is required to maintain warranty. This unit uses R-454B (A2L) refrigerant; installation, charging, and service must be performed by an EPA Section 608-certified technician. Upon timely registration, Carrier's Consumer Choice Warranty offers eligible equipment either a 10-year parts-only limited warranty or a 5-year parts plus 3-year labor limited warranty — confirm exact eligible terms for this model in the manufacturer resources tab.
