Mitsubishi PAA-BA42NL & PUY-AK42NL 42,000 BTU 17.1 SEER2 Cased Coil Cooling Only System - R454B

Mitsubishi PAA-BA42NL & PUY-AK42NL: 42,000 BTU Split-System Air Conditioner

The Mitsubishi PAA-BA42NL indoor cased coil paired with the PUY-AK42NL outdoor condenser delivers powerful, energy-efficient cooling for residential and light commercial applications. Designed for compatibility with gas furnace systems and hybrid HVAC installations, this 42,000 BTU split-system air conditioner combines Mitsubishi’s advanced inverter-driven technology, flexible installation options, and durable construction to provide reliable comfort and exceptional cooling performance throughout the season.

The PAA-BA42NL indoor unit is engineered for compatibility with most ANSI-certified gas furnaces and supports Mitsubishi intelli-HEAT® technology, allowing intelligent integration within hybrid HVAC systems. While paired with a cooling-only outdoor condenser, the indoor unit is designed to support future system flexibility and advanced comfort solutions. A high-quality drain pan with excellent heat tolerance and low moisture absorption helps ensure long-term reliability and dependable operation. Flexible multi-position installation supports horizontal left, horizontal right, upflow, and downflow configurations, making the unit ideal for both retrofit projects and new construction applications.

The PUY-AK42NL outdoor condenser utilizes Mitsubishi’s INVERTER-driven twin rotary compressor technology to precisely match cooling demand. Unlike traditional single-stage air conditioners, inverter technology continuously adjusts compressor speed to maintain more consistent indoor temperatures, improve efficiency, reduce energy consumption, and minimize temperature swings. With a rated cooling capacity of 42,000 BTU and a maximum capacity of 43,000 BTU, the system delivers powerful cooling performance for larger residential and light commercial spaces.

Built for long-term durability, the outdoor unit incorporates Blue Fin anti-corrosion coating and Seacoast Protection to help protect the heat exchanger from salt, sulfur, and airborne contaminants. These features make the system particularly well suited for coastal environments and other demanding outdoor conditions. The condenser supports cooling operation in outdoor temperatures from 23°F up to 115°F, ensuring dependable performance across a wide range of climates and applications.

Despite its robust cooling capacity, the system maintains quiet operation with outdoor sound levels as low as 52 dB(A). Advanced control options support Mitsubishi Comfort app connectivity, kumo station®, BACnet® and Modbus® interfaces, wired and wireless remote controllers, remote temperature sensors, and third-party thermostat integration for flexible comfort management and building automation compatibility.

General Information

System Type: Cased coil indoor unit + single-zone cooling-only outdoor condenser

Models: Indoor – PAA-BA42NL | Outdoor – PUY-AK42NL

Capacities: 42,000 BTU Rated Cooling (Max 43,000 | Min 15,400)

Room Size: Ideal for residential and light commercial spaces up to ~2,000–2,500 sq ft

Operating Modes: Cooling Only

ENERGY STAR®: No

Refrigerant / Factory Charge: R-454B, 9 lb 14 oz (pre-charged for 100 ft line length)

Key Features

INVERTER-Driven Compressor: Precise cooling output for improved comfort and efficiency

Twin Rotary Compressor: Smooth, reliable, and energy-efficient operation

intelli-HEAT® Compatible Indoor Unit: Supports hybrid HVAC applications with compatible equipment

High Airflow Performance: Up to 1,660 CFM indoor airflow

Blue Fin Coating: Corrosion-resistant outdoor heat exchanger protection

Seacoast Protection: Enhanced durability in coastal and harsh environments

Quiet Operation: Outdoor sound levels as low as 52 dB(A)

Flexible Installation: Multi-position indoor installation configurations

Cooling Operation Range: Outdoor temperatures from 23°F to 115°F

Smart Controls: Comfort app compatibility, wired/wireless remotes, thermostat and building automation interfaces

Specifications (Rated Conditions)

Cooling Capacity: 42,000 BTU (Max 43,000 | Min 15,400) | SEER2: 17.1 | EER2: 10.3

Electrical: 208/230 V, 1-Ph, 60 Hz | Outdoor MCA: 34 A | MOCP: 56 A

Indoor Airflow: 936–1,660 CFM

Outdoor Sound: 52 dB(A) Cooling

Piping: Liquid 3/8 in | Gas 5/8 in | Max line length: 100 ft | Max height: 100 ft

Outdoor Operating Range: 23°F to 115°F Cooling Ambient

Outdoor Dimensions / Weight: 41-11/32 × 14 × 52-43/64 in | 224 lb

Indoor Dimensions / Weight: 17-1/2 × 21-3/8 × 32 in | 72.8 lb (cased coil)

Drain Connection: 3/4 in O.D.

Included Components

Indoor Unit: PAA-BA42NL cased coil indoor unit

Outdoor Unit: PUY-AK42NL inverter-driven air conditioning condenser

Ideal For

Homes and light commercial spaces seeking high-capacity, energy-efficient cooling with advanced inverter technology and flexible furnace compatibility. The Mitsubishi PAA-BA42NL & PUY-AK42NL system delivers powerful cooling performance, precise temperature control, quiet operation, corrosion-resistant durability, and dependable comfort for larger applications.