Mitsubishi Electric 24,000 BTU 20 SEER2 Dual Zone Wall Mounted Ductless Mini Split Heat Pump System 9+12 R454B Refrigerant | MXZ-3D24NL-MSZ-GX09NL-MSZ-GX12NL

Overview

This Mitsubishi Electric bundled ductless heat pump system centers on the MXZ-3D24NL outdoor unit, a 23,600 BTU/h class multi-zone condenser designed for zoned heating and cooling. It operates on 208/230V, 1 phase, 60Hz and uses R454B refrigerant in a factory-charged outdoor section. The outdoor unit supports 2 to 3 connected indoor zones and uses a variable-speed INVERTER-driven twin rotary compressor for capacity modulation. Rated cooling capacity is 22,000 Btu/h with a rated heating capacity of 25,000 Btu/h at 47°F, supporting year-round comfort in multi-room layouts. This configuration is built as a single product combining the outdoor unit with 1 × MSZ-GX09NL wall-mounted indoor unit (9,000 BTU nominal cooling, 10,900 BTU nominal heating); 1 × MSZ-GX12NL wall-mounted indoor unit (12,000 BTU nominal cooling, 14,400 BTU nominal heating). Outdoor airflow is 2,119 CFM in cooling and 2,228 CFM in heating for steady heat exchanger performance.

Performance

Efficiency is listed at up to 20 SEER2, 13.7 EER2, and 10 HSPF2 in non-ducted configurations, supporting lower operating cost when zoning is used effectively. The outdoor section delivers a maximum heating capacity of 30,600 Btu/h at 47°F and a maximum cooling capacity of 22,000 Btu/h at 95°F test conditions. Reverse-cycle defrost helps maintain heating operation in cold weather while protecting coil performance. Blue Fin heat exchanger coating is applied for corrosion protection, and the outdoor unit is rated for 2,000 hours spraying time per ASTM B117. Maximum total refrigerant piping length is 230 ft with up to 82 ft to the farthest indoor run and up to 49 ft of outdoor-to-indoor height difference. Outdoor protection functions include high-pressure protection, compressor thermal protection, and compressor overcurrent detection to support stable operation.

Smart Features

Wi‑Fi enabled indoor units support control through the Mitsubishi Electric Comfort app for setpoint, mode, fan speed, and scheduling management. A back‑lit handheld remote controller is provided with the indoor units for local zone control without additional accessories. Control options support wireless and wired controllers, plus third‑party interface modules for system integration where required. Fan speed selections include Low, Medium, High, Powerful, and Auto, giving control flexibility for fast pull‑down or steady operation. Smart Set allows a stored preferred setting to be recalled, and Econo Cool adjusts airflow based on heat exchanger temperature for energy-aware comfort. Smart Dry Mode improves humidity management with minimal over‑cooling during cooling operation.

Comfort and Noise

Outdoor sound pressure is listed at 51 dB(A) in cooling and 55 dB(A) in heating, supporting placement near living areas when clearances allow. Indoor sound performance varies by indoor unit model; MSZ-GX09NL sound pressure ranges from 19 to 43 dB(A) across fan speeds; MSZ-GX12NL sound pressure ranges from 19 to 45 dB(A) across fan speeds. Indoor airflow capability supports even temperature distribution, with MSZ-GX09NL provides up to 448 CFM airflow at cooling dry conditions; MSZ-GX12NL provides up to 448 CFM airflow at cooling dry conditions. Powerful Mode temporarily adjusts setpoint and fan speed to reach the desired room condition more quickly when rapid recovery is needed. The DC fan motor design supports multiple fan speed steps for low-noise operation at reduced airflow and higher output during peak loads. Dual Barrier Coating is applied to the indoor unit airflow path to reduce contaminant buildup on internal surfaces and maintain airflow over time.

Use Case Fit

This system is well-suited to residential multi-room zoning, condo and multi-family applications, and light commercial spaces needing individual room control. The outdoor unit operating range supports cooling intake air temperatures from 14°F to 115°F. Heating intake air temperatures are listed from 6°F up to 75°F, supporting shoulder-season and winter operation depending on climate. The outdoor platform supports prolonged heating over an extended duration, helping maintain comfort during sustained heating demand. Because zones can operate independently, the system fits homes where occupancy patterns vary by room and conditioning can be targeted. Electrical requirements of 208/230V single-phase support use across standard North American residential and light commercial service conditions.

Value and Reliability

Reliability features include fan motor overheating and voltage protection, high-pressure protection, and compressor safeguards designed to reduce fault conditions. Blue Fin coil protection and seacoast-rated corrosion measures are specified for environments where outdoor exposure can degrade standard coils. Defrost is handled through reverse cycle operation to manage frost accumulation while maintaining heat output. The outdoor chassis is compact for multi-zone applications, with a small footprint compared with multiple single-zone condensers. Base pan heat is optional on the standard model and built-in on the Hyper-Heat model, supporting drainage management during cold-weather operation. Electrostatic enzyme filtration is built into the indoor units, with optional microparticle filtration available to address non-living particulates such as dust and smoke.

Summary Wrap-Up

With a multi-zone outdoor unit and wall-mounted indoor heads, this Mitsubishi Electric configuration provides zoned comfort without requiring ductwork. Capacity modulation from the inverter-driven compressor supports steady temperature control and avoids the on/off swings of fixed-speed equipment. Outdoor operating ranges and reverse-cycle defrost expand heating usability across a broad range of outdoor conditions. Control options through handheld remotes and app-based management support both homeowner convenience and contractor-friendly commissioning workflows. Coil protection and built-in safety functions support long service life in typical residential and light commercial environments. For D2C buyers and HVAC professionals, the combination of zoning flexibility, published performance ratings, and Mitsubishi Electric platform compatibility supports confident system selection.

Key Features

• R454B refrigerant charge: Uses R454B refrigerant with a factory pre-charge of 5 lb 5 oz in the outdoor unit for multi-zone operation.
• INVERTER-driven twin rotary compressor: Modulates capacity to match zone demand and supports stable temperature control across connected indoor units.
• Multi-zone connection design: Supports 2 to 3 connected indoor units with maximum connected capacity listed at 28,000 Btu/h and total piping length up to 230 ft.
• Outdoor airflow and sound data: Outdoor airflow is listed at 2,119 CFM cooling and 2,228 CFM heating with sound pressure of 51 dB(A) cooling.
• Indoor filtration and coating system: Dual Barrier Coating supports cleaner airflow paths and indoor units include an electrostatic enzyme filter with optional microparticle filtration.
• Wi‑Fi and controller options: Comfort app control and a back‑lit handheld remote controller support zone scheduling, mode selection, and fan speed management.