MRCOOL Signature Series 3.5 Ton Multi-Position Air Handler | MCAEAMPEF42C21AA
MRCOOL Signature Series 3.5 Ton Multi-Position Air Handler | MCAEAMPEF42C21AA
Summary
The MRCOOL® Signature Series 42k Multi-Position Air Handler is built to provide consistent, energy-efficient comfort in any climate. Designed for flexibility and performance, this unit works with R-454B refrigerant, a low-GWP alternative that helps reduce environmental impact without sacrificing power or reliability. Its multi-position design allows for installation in upflow, downflow, or horizontal configurations, making it ideal for a variety of home layouts, from new construction to tight retrofits. With its slim, space-saving profile, it fits easily into closets, attics, or crawl spaces while still delivering full-capacity heating and cooling when paired with a compatible condenser or heat pump. Engineered for durability, the air handler includes a galvanized steel cabinet, a high-efficiency ECM blower motor, and copper "A" coils with enhanced aluminum fins for superior heat transfer and humidity control. Thermal insulation inside the cabinet reduces energy loss and prevents condensation, contributing to quiet operation and lower energy bills. Installation is fast and simple, helping to minimize labor time and disruption. An air filter rack allows for easy maintenance, while an optional electric heat kit is available for added heating performance in colder regions. Smart home compatibility comes standard, with support for most third-party thermostats so you can manage comfort on your terms; no proprietary systems required. Protected by a 10-year limited parts warranty, the MRCOOL® Signature Series 42k Multi-Position Air Handler offers long-lasting performance, space-saving design, and year-round efficiency for today's comfort-conscious homeowner.
Important
AHRI certified - meets industry standards. Register your product to activate warranty coverage. This air handler contains R-454B refrigerant, which is classified as an A2L refrigerant. To comply with safety standards, this unit must be paired with an R-454B condenser equipped with a leakage detection system. Failure to comply with these requirements may result in safety hazards and could void the warranty.
Key Features
- 42,000 BTU capacity (3.5 Ton)
- Multi-position installation (upflow, downflow, horizontal)
- Low-GWP R-454B refrigerant
- High-efficiency ECM blower motor
- Quiet operation (54 dBA)
- Durable galvanized steel cabinet
- Copper "A" coils with enhanced aluminum fins
- Built-in air filter rack for easy maintenance
- Compatible with most third-party thermostats
- Optional electric heat kit available
- Internal thermal insulation
- AHRI certified
- 5-speed blower motor for precise airflow control
Complete Technical Specifications
| Brand | MRCOOL |
| Series | Signature Series Multi-Position Air Handler |
| Model | MCAEAMPEF42C21AA |
| UPC | 840255595889 |
| GTIN | 00840255595889 |
| Unit Type | Air Handler |
| Configuration | Multi-Position |
| Certifications | UL Listed, CSA Listed, ETL Listed, AHRI Certified |
| Capacity | 42,000 BTU (3.5 Ton) |
| CFM | 1254 |
| Refrigerant | R-454B |
| Electrical | 208/230V 1 Phase 60 Hz |
| Min Circuit Ampacity | 7.2A |
| Max Fuse Breaker | 10A |
| Blower Motor Type | ECM |
| Blower Motor HP | 3/4 |
| Blower Motor Speeds | 5 |
| Blower Motor RPM | 1040 |
| Sound Rating | 54 dBA |
| Liquid Line Size | 3/8" |
| Suction Line Size | 3/4" |
| Drain Connection Size | 3/4" |
| Filter Type | Replaceable |
| Filter Size | 18" x 21" x 1" |
| Metering Device | Orifice |
| Auxiliary Heater Included | No |
| Auxiliary Heater Available | Yes (5kW, 7.5kW, 10kW) |
| Net Dimensions (HxWxD) | 45.75" x 19.625" x 22" |
| Net Weight | 131 lbs |
| Shipping Dimensions | 47.875" x 22.83" x 25.6" |
| Shipping Weight | 144 lbs |
Performance Features
| Compatible Equipment | Signature Series Top Discharge Condensers |
| Installation Flexibility | Multi-position (upflow, downflow, horizontal) |
| Refrigerant | Low-GWP R-454B refrigerant for reduced environmental impact |
| Motor Technology | High-efficiency ECM blower motor |
| Noise Reduction | Quiet operation (54 dBA) |
| Coil Technology | Copper "A" coils with enhanced aluminum fins |
| Cabinet Construction | Durable galvanized steel |
| Speed Control | 5-speed motor for precise airflow adjustment |
| Airflow Capacity | High-capacity 1254 CFM for maximum performance |
| Smart Home Compatibility | Works with most third-party thermostats |
| Heating Options | Optional electric heat kits (5kW, 7.5kW, 10kW) |
Warranty Information
- Registered Warranty: 10 years parts, limited lifetime compressor
- Base Warranty: 10 years parts, limited lifetime compressor
- Registration may be required for full warranty coverage
Manuals & Certifications
Safety Information
PROPOSITION 65 WARNING: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.
Advanced Technology
The MRCOOL Signature Series 42k Multi-Position Air Handler features advanced ECM motor technology with a powerful 3/4 HP motor that delivers superior energy efficiency and precise airflow control across five speed settings. The copper "A" coils with enhanced aluminum fins provide exceptional heat transfer and humidity control for optimal indoor comfort in larger residential and light commercial applications. The durable galvanized steel cabinet ensures long-lasting performance, while comprehensive thermal insulation minimizes energy loss and prevents condensation. Operating at just 54 decibels, this 3.5-ton air handler maintains remarkably quiet performance despite its substantial 1254 CFM airflow capacity. The ECM motor's intelligent operation automatically adjusts airflow to maintain optimal system performance, while compatibility with most third-party thermostats enables seamless integration into modern smart home ecosystems for complete comfort control.
Installation Advantages
This 3.5-ton air handler provides exceptional installation versatility with true multi-position capability for upflow, downflow, or horizontal configurations, making it ideal for space-constrained installations in attics, closets, and crawlspaces. The high-efficiency ECM motor delivers superior performance with lower energy consumption while handling the substantial 1254 CFM airflow requirement for larger homes. The built-in air filter rack simplifies routine maintenance with easy access for quick filter replacements. The unit's streamlined design minimizes installation time and labor costs, while multiple optional electric heat kit sizes (5kW, 7.5kW, or 10kW) provide flexible heating capacity for various climate requirements. With its compact footprint and comprehensive compatibility with Signature Series Top Discharge Condensers, this air handler represents a premium, energy-efficient solution for residential and light commercial HVAC systems requiring robust performance in demanding applications and larger spaces.
