Mitsubishi MSZ-WX12NL & MUZ-WX12NL 12,000 BTU 18 SEER2 Wall Mounted Heat Pump System - R454B

Mitsubishi MSZ-WX12NL & MUZ-WX12NL: 12,000 BTU Wall-Mounted Heat Pump System

The Mitsubishi MSZ-WX12NL indoor unit, paired with the MUZ-WX12NL outdoor condenser, delivers efficient 12,000 BTU heating and cooling in a compact, single-zone ductless mini-split system. Engineered for rooms up to 500 sq ft, this unit features Heating INVERTER technology for reliable performance in extreme cold, maintaining warmth down to -13°F outdoor temperatures.

This ENERGY STAR® certified system uses environmentally friendly R-454B refrigerant and features a sleek, wall-mounted design with a built-in washable filter and whisper-quiet operation. Built-in Wi-Fi and advanced smart control compatibility provide flexible remote access and temperature scheduling.

General Information
System Type: Wall-mounted ductless air handler + single-zone heat pump condenser
Models: Indoor – MSZ-WX12NL | Outdoor – MUZ-WX12NL
Capacities: 12,000 BTU Cooling | 12,200 BTU Heating
Room Size: Ideal for 500 sq ft
Operating Modes: Heating & Cooling
ENERGY STAR®: Yes
Refrigerant / Factory Charge: R-454B, 2.20 lb

Key Features

• INVERTER Technology: Precise, energy-saving heating and cooling

• Heat Performance: Delivers warmth in extreme cold, down to -13°F

• Compact Design: Slim indoor unit fits tight spaces and blends into decor

• Quiet Operation: Indoor sound levels as low as 22 dB(A)

• Washable Filter: Long-lasting, easy-to-clean air filtration

• Built-In Wi-Fi: Compatible with Comfort app, wired and wireless controllers

Specifications (Rated Conditions)
Cooling Capacity: 12,000 BTU | EER2: 9 | SEER2: 18
Heating Capacity @ 47°F: 12,200 BTU | HSPF2: 8.5 | COP (47°F): 3.28
Heating Capacity @ 17°F: 7,500 BTU
Electrical: 208/230 V, 1-Ph, 60 Hz | MCA: 8 A | MOCP: 15 A
Airflow (Dry): 147-391 CFM
Sound Pressure: Indoor 22–45 dB(A) | Outdoor 51 dB(A)
Piping: Liquid 1/4 in. | Gas 3/8 in. | Max line length: 65 ft | Max height: 40 ft
Outdoor Dimensions / Weight: 31-1/2 x 11-1/4 x 21-5/8 in. | 20 lb
Drain Connection: 5/8 in. O.D.

Included Components

• Indoor Unit: MSZ-WX12NL wall-mounted air handler

• Outdoor Unit: MUZ-WX12NL Hyper Heat heat pump condenser

• Hand-Held Remote Controller

Ideal For
Homeowners and contractors seeking a premium, energy-efficient solution for year-round comfort in bedrooms, offices, or smaller living areas. The MSZ-WX12NL & MUZ-WX12NL deliver powerful, quiet heating and cooling in a sleek, reliable design.