MRCOOL® Signature Series 42K (3.5 Ton) Split AC System — MCAEAMPEF42C21AA + MCAESAS4T4221AA
Overview
The MRCOOL® Signature Series 42K split system pairs a multi-position air handler with a cooling-only condenser for dependable, energy-conscious cooling. The air handler supports upflow, downflow, and horizontal configurations and uses a high-efficiency ECM blower motor for strong airflow and efficient comfort delivery. Both components use R-454B refrigerant for a modern, low-GWP refrigerant platform.
Highlights
- Multi-position install: Air handler supports upflow, downflow, and horizontal configurations for flexible layouts.
- ECM comfort control: High-efficiency ECM blower (5 speeds) supports strong airflow and better comfort control.
- Efficient cooling: Condenser rated 14.3 SEER2 and 11.7 EER2.
- Quiet-minded design: Outdoor unit listed at 65 dB(A) with a sound-dampening top.
- Long-line capable: Condenser lists up to 150 ft maximum line set length.
3.5 Ton (42K Class)
1254 CFM (Indoor)
3/8" Liquid • 3/4" Suction
150 ft
Sizing and performance depend on installation, duct design, and load. Manual J sizing is recommended.
What’s Included
- Multi-Position Air Handler: MCAEAMPEF42C21AA
- Cooling-Only Condenser: MCAESAS4T4221AA
- Documentation (see Documents & Downloads)
Indoor Specs
Model: MCAEAMPEF42C21AA (Signature Series Multi-Position Air Handler)
| Unit Type | Air Handler |
| Configuration / Mount | Multi-Position (Upflow / Downflow / Horizontal) |
| Tonnage | 3.5 Ton |
| Airflow (CFM) | 1254 |
| Sound | 54 dB(A) |
| Refrigerant | R-454B |
| Metering Device | Orifice |
| Drain Connection Size | 3/4" |
| Line Sizes | Liquid 3/8" • Suction 3/4" |
| Blower Motor Type | ECM |
| Blower Motor | 3/4 HP • 5 Speeds • 1040 RPM |
| Filter | Replaceable • 18" × 21" × 1" |
| Electrical | 208/230V • 1-Phase • 60 Hz |
| Min Circuit Ampacity (MCA) | 7.2A |
| Max Fuse / Breaker | 10A |
| Aux Heat | Not included • Optional heat kit available (5 kW, 7.5 kW, 10 kW) |
| Certifications | UL Listed • CSA Listed • ETL Listed • AHRI Certified |
| Color | Grey |
| Dimensions (W×D×H) | 19.625" × 22" × 45.75" |
| Net Weight | 131 lb |
| GTIN / UPC | GTIN 00840255595889 • UPC 840255595889 |
| Proposition 65 | Yes |
Designed to work with Signature Series top discharge condensers and most third-party thermostats.
Outdoor Specs
Model: MCAESAS4T4221AA (Signature Series Split System AC Condenser — Cooling Only)
| Unit Type | Split System AC Condenser (Cooling Only) |
| Tonnage | 3.5 Ton |
| Cooling Capacity | 39,000 BTU |
| Efficiency | 14.3 SEER2 • 11.7 EER2 |
| Airflow (CFM) | 2950 |
| Sound | 65 dB(A) |
| Inverter | No |
| Min Ambient Cooling | 59°F |
| Refrigerant | R-454B • 114.6 oz |
| Max Line Set Length | 150 ft |
| Line Sizes | Liquid 3/8" • Suction 3/4" |
| Compressor | Scroll |
| Condenser Fan Motor | PSC • 1/7 HP |
| Electrical | 208/230V • 1-Phase • 60 Hz |
| Min Circuit Ampacity (MCA) | 26A |
| Max Fuse / Breaker | 45A |
| Certifications | UL Listed • CSA Listed • ETL Listed • AHRI Certified |
| Color | Grey |
| Dimensions (W×D×H) | 29.14" × 29.14" × 32.875" |
| Net Weight | 185 lb |
| GTIN / UPC | GTIN 00840255595957 • UPC 840255595957 |
| Proposition 65 | Yes |
Designed to work with Signature Series Multi-Position or Stud Mount air handlers.
Documents & Downloads
- Signature Series Multi-Position Air Handler (MCAEAMPEF42C21AA)
- Signature Series Cooling-Only Condenser (MCAESAS4T4221AA)
Important
- Cooling-only outdoor unit: This condenser is listed as cooling only. If you need heating via outdoor equipment, select a compatible heat pump condenser instead.
- Line sizes: Listed as 3/8" liquid and 3/4" suction; confirm routing and any long-line requirements in the installation manual.
- Line set length: Condenser lists up to 150 ft maximum line set length; verify long-line accessories/requirements in the install manual.
- Electrical: Both components are 208/230V, 1-phase, 60 Hz. Verify breaker/fuse sizing per install manual and local code.
- Air handler orientation: Supports upflow, downflow, and horizontal installation; configure condensate management for the selected position.
- Optional heat kits: Supported sizes listed as 5 kW, 7.5 kW, and 10 kW (sold separately).
FAQs
Is this a heat pump system?
No. The outdoor unit in this pairing is a cooling-only condenser. Heating requires a different outdoor unit (heat pump) or an indoor heat source such as an optional electric heat kit.
What installation positions does the air handler support?
The air handler is multi-position and supports upflow, downflow, and horizontal configurations.
What refrigerant and line sizes does it use?
Refrigerant is listed as R-454B. Line sizes are 3/8" liquid and 3/4" suction.
What is the maximum line set length?
The condenser lists a maximum line set length of 150 ft.
What warranty coverage is included?
Warranty is listed as 10-year limited parts, with limited lifetime compressor coverage referenced for the outdoor unit.
