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MRCOOL

MRCOOL Signature 3.5 Ton 42K BTU Cooling Only Central Ducted Split System

SKU: MCAESAS4T4221AA + MCAEAMPEF42C21AA

System highlights
AC Type
AC Air Handler Systems
Refrigerant Type
R454B
Brand
MRCOOL
Outdoor Unit
42000 BTU VO (3.5 TON)
Indoor Unit
42000 BTU (3.5 TON)
Voltage
208-230V
Looking For
Ducted
Series
Singnature Series
SEER2 Rating
13.8

Price

$3,389.39
Shipping calculated at checkout.
Quantity
View full details
MRCOOL — Signature Series Split System (Air Handler + Cooling-Only Condenser)

MRCOOL® Signature Series 42K (3.5 Ton) Split AC System — MCAEAMPEF42C21AA + MCAESAS4T4221AA

Overview

42K Class 3.5 Ton Up to 14.3 SEER2 11.7 EER2 R-454B Cooling Only Multi-Position Air Handler Upflow / Downflow / Horizontal ECM Blower AHRI Certified 10-Year Parts Warranty

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.
System Size
3.5 Ton (42K Class)
Airflow
1254 CFM (Indoor)
Line Sizes
3/8" Liquid • 3/4" Suction
Max Line Set
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

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.