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Mitsubishi Concealed Duct 3-Zone System - 42,000 BTU Outdoor - 12k + 12k + 18k Indoor - 15.2 SEER2
Model:
M3H42D12121800-B
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Recommended Accessories
Expert Recommended Accessories
Selected by Ken, our Expert
Required Accessories
9
These accessories are required to properly setup/install this product.
Optional Accessories
10
Features
- Precision Temperature Control Technology
- The MXZ-5C42NA4 outdoor condenser is equipped with inverter technology and an electronic linear expansion valve. These components improve temperature accuracy and system efficiency through precise adjustments of both compressor speed and refrigerant flow.
- Hot-Start
- Mitsubishi's hot-start technology prevents cold drafts by delaying fan operation until the heat exchanger has warmed up.
- Dehumidification
- When the indoor unit runs in dry mode, the coil's temperature stays just below the dew point of the return air, removing unwanted moisture. This improves your comfort and reduces both mold growth and the chance of property damage in the conditioned space.
- Condensate Removal System
- The included SEZ-KD compact duct indoor units contain an internal drain mechanism capable of lifting condensate 21-11/16". This simplifies installation and prevents condensate overflow, which can damage or destroy your property.
- Advanced Remote Controller
- The MHK1 remote controller kits have dual set point control and multiple scheduling options. They learn how quickly your zones are cooled and heated and adjust scheduled operations so that the zones are always the right temperature at the right time.
- Inconspicuous Design
- Installing a source of zoned comfort doesn't have to disrupt the visual layout of your space. With the concealed duct units, small air registers are the only evidence that a powerful and efficient mini split system is servicing your rooms.
- Recommended line set sizes for indoor unit connectivity:
- SEZ-KD12NA4R1.TH: 1/4" x 3/8" Line Set (Qty 2)
- SEZ-KD18NA4R1.TH: 1/4" x 1/2" Line Set
- (1) Mitsubishi - 42k BTU - M-Series Outdoor Condenser - For 2-5 Zones (MXZ-5C42NA4)
- (1) Mitsubishi 18,000 BTU Ducted Horizontal Heat Pump Air Handler (SEZ-KD18NA4R1.TH)
- (2) Mitsubishi 12,000 BTU Ducted Horizontal Heat Pump Air Handler (SEZ-KD12NA4R1.TH)
- (3) Mitsubishi RedLINK - Wireless Remote Controller Kit - Programmable - Wall Mounted (MHK2)
- Line Set - This double insulated tubing transfers refrigerant efficiently between your outdoor condenser and indoor units.
- Drain Tubing - Drain tubing facilitates the reliable and effective removal of condensate from your system. It connects your indoor units to drain locations of your choosing. We recommend locally purchased PVC hard pipe for the condensate drain on cassette and concealed duct units.
- Disconnect Box & Electrical Whip Kit - The Disconnect Box & Whip Kit provides a safe and simple way to connect your outdoor condenser to your fuse box.
- Connecting Wire - This durable, insulated wire provides power to your indoor units from your outdoor condenser.
- Base Pan Heater - The base pan heater prevents ice from building up on the outdoor unit. Excessive ice build will lead to performance issues and could damage your unit.
- Outdoor Condenser Plastic Pad or Wall Bracket - We recommend outdoor condensers should not be placed directly on the ground. An outdoor condenser pad or wall bracket will provide a stable way to mount your condenser free from obstructions and debris.
For over 50 years, Mitsubishi has remained at the forefront of the mini split industry thanks to their dedication to providing efficient, user-friendly comfort solutions. This is a three zone mini split system designed to give you individual control over the temperature in multiple rooms. An efficient MXZ-5C42NA4 outdoor condenser, built with advanced technology, is combined with unobtrusive concealed duct SEZ-KD indoor units and three wireless remote controllers for the perfect marriage of convenience and comfort. With multiple operating modes and multiple fan speeds, this is a system that fits the needs of nearly any home.
Product Includes
Product Note
This product requires the following accessories for installation:
Specifications
Product Includes
- (1) Mitsubishi - 42k BTU - M-Series Outdoor Condenser - For 2-5 Zones (MXZ-5C42NA4)
- (1) Mitsubishi 18,000 BTU Ducted Horizontal Heat Pump Air Handler (SEZ-KD18NA4R1.TH)
- (2) Mitsubishi 12,000 BTU Ducted Horizontal Heat Pump Air Handler (SEZ-KD12NA4R1.TH)
- (3) Mitsubishi RedLINK - Wireless Remote Controller Kit - Programmable - Wall Mounted (MHK2)
M3H42D12121800-B
Overview
Product Category
Mini Split Heat Pump System
General Information
Type
Concealed Duct
Product Line
M-Series
Product Category
Mini Split Heat Pump System
Operating Mode
Operating Mode
Some products are only capable of cooling, while others can either heat or cool a space. Some products heat via "heat pump" technology while others use electric heating elements. Learn More
Heating and Cooling
Number of Zones
Number of Zones
A zone is a room or area within a building that has its own temperature control.
3
Refrigerant Type
R-410A
Indoor Unit Size(s)
Indoor Unit Size(s)
Mini split systems can have one or more indoor units connected to a single outdoor unit. Indoor Unit Size(s) specifies what indoor unit sizes are used in a system. We have combined 6k and 7k indoor units to enhance searchability.
12 + 12 + 18
Outdoor Unit Size
42000 BTU
DOE Regional Compliance
DOE Regional Compliance
In 2015, the US Department of Energy broke the country into three regions - North, Southeast, and Southwest - and set legal standards for energy efficiency within each region. Learn More
Nationwide
Performance
Low Ambient Heating
No
Minimum Outdoor Temperature for Heating
Minimum Outdoor Temperature for Heating
This is the lowest rated outdoor temperature for heating operation. Because heat pumps rely on heat available in outdoor air, the amount of heat they are able to supply decreases with outdoor temperatures. Learn More
5 F
Minimum Outdoor Temperature for Cooling
14 F
SEER2
SEER2
The U.S Department of Energy has raised the minimum rating requirements starting in 2023 that include updated testing conditions and metrics to better reflect real-world conditions. SEER2 (Seasonal Energy Efficiency Ratio) is a measurement of cooling efficiency over a typical cooling season. It is useful for comparing energy efficiency of cooling systems. The higher the SEER2, the more energy efficient the system.
15.2
EER2
EER2
The U.S Department of Energy has raised the minimum rating requirements starting in 2023 that include updated testing conditions and metrics to better reflect real-world conditions. EER2 (Energy Efficiency Ratio) is a measurement of cooling efficiency under fixed conditions. It is useful for comparing units that will operate consistently under one set of conditions (e.g. server room). The higher the EER2, the more efficient the system.
9.0
HSPF2
HSPF2
The U.S Department of Energy has raised the minimum rating requirements starting in 2023 that include updated testing conditions and metrics to better reflect real-world conditions. HSPF2 (Heating Seasonal Performance Factor) is a measure of heating efficiency for heat pumps. It is useful for comparing energy efficiency of heat pumps. The higher the HSPF2, the more efficient the system.
8.3
Dimensions
Product Weight
381 Pounds
Shipping Weight
385 Pounds
Certifications
ETL Listed
Yes
AHRI Certified
Yes
AHRI Reference Number
212925486
MXZ-5C42NA4
General Information
Type
Outdoor Condenser
Product Line
M-Series
Product Category
Mini Split System Components
Operating Mode
Operating Mode
Some products are only capable of cooling, while others can either heat or cool a space. Some products heat via "heat pump" technology while others use electric heating elements. Learn More
Heating and Cooling
Maximum Number of Zones
5
Multi-Zone Compatible
Yes
Refrigerant Type
R-410A
Installation Location
Outdoor
Base Pan Heater Included
No
Performance
Cooling BTU
42000
Cooling Capacity
43000 BTU
Heating Capacity
53600 BTU
Maximum Sound Level
Maximum Sound Level
Sound levels are measured in decibels (dB). The lower the decibel rating, the less noise the product makes. As an example, a ticking watch is 20 dB while on the other end of the scale, a lawn mower is around 90 dB. Learn More
58 dB
Low Ambient Heating
No
Minimum Outdoor Temperature for Heating
Minimum Outdoor Temperature for Heating
This is the lowest rated outdoor temperature for heating operation. Because heat pumps rely on heat available in outdoor air, the amount of heat they are able to supply decreases with outdoor temperatures. Learn More
5 F
Minimum Outdoor Temperature for Cooling
14 F
Electrical Data
Voltage
208/230 Volts
Phase
1
Frequency
60 Hz
Minimum Circuit Ampacity
32.5 Amps
Recommended Breaker Size
40 Amps
Dimensions
Maximum Line Length
262 Feet
Line Set A Liquid Connection
1/4 Inch
Line Set A Gas Connection
1/2 Inch
Line Set B Liquid Connection
1/4 Inch
Line Set B Gas Connection
3/8 Inch
Line Set C Liquid Connection
1/4 Inch
Line Set C Gas Connection
3/8 Inch
Line Set D Liquid Connection
1/4 Inch
Line Set D Gas Connection
3/8 Inch
Line Set E Liquid Connection
1/4 Inch
Line Set E Gas Connection
3/8 Inch
Product Height
41 13/48 Inches
Product Width
37 19/48 Inches
Product Depth
13 Inches
Product Weight
189 Pounds
Shipping Height
48 7/16 Inches
Shipping Width
41 3/8 Inches
Shipping Depth
17 3/8 Inches
Shipping Weight
218 Pounds
Certifications
ETL Listed
Yes
Warranty Information
Parts Warranty
Parts Warranty
A warranty is a safeguard from defects in manufacturing and can vary in length and terms. Some manufacturers require registration for extended warranty benefits, be sure to check out features and the warranty document. To see the manufacturer's warranty statement, click on the Manuals tab. Learn More
5 Years
Compressor Warranty
7 Years
SEZ-KD18NA4R1
General Information
Type
Concealed Duct
Product Line
M-Series
Product Category
Mini Split System Components
Operating Mode
Operating Mode
Some products are only capable of cooling, while others can either heat or cool a space. Some products heat via "heat pump" technology while others use electric heating elements. Learn More
Heating and Cooling
Multi-Zone Compatible
Yes
Refrigerant Type
R-410A
Indoor Unit Size(s)
Indoor Unit Size(s)
Mini split systems can have one or more indoor units connected to a single outdoor unit. Indoor Unit Size(s) specifies what indoor unit sizes are used in a system. We have combined 6k and 7k indoor units to enhance searchability.
18
Installation Location
Indoor
Performance
Cooling BTU
18000
Cooling Capacity
17200 BTU
Moisture Removal
3.4 Pints/Hour
Maximum Air Flow
635 CFM
Minimum Air Flow
423 CFM
Minimum Sound Level
30 dB
Maximum Sound Level
Maximum Sound Level
Sound levels are measured in decibels (dB). The lower the decibel rating, the less noise the product makes. As an example, a ticking watch is 20 dB while on the other end of the scale, a lawn mower is around 90 dB. Learn More
38 dB
Electrical Data
Phase
1
Frequency
60 Hz
Dimensions
Gas Connection Size
1/2 Inch
Liquid Connection Size
1/4 Inch
Product Height
7 7/8 Inches
Product Width
46 7/8 Inches
Product Depth
27 9/16 Inches
Product Weight
72 Pounds
Shipping Weight
82 Pounds
Certifications
ETL Listed
Yes
Warranty Information
Parts Warranty
Parts Warranty
A warranty is a safeguard from defects in manufacturing and can vary in length and terms. Some manufacturers require registration for extended warranty benefits, be sure to check out features and the warranty document. To see the manufacturer's warranty statement, click on the Manuals tab. Learn More
5 Years
Overview
Product Category
Mini Split System Components
SEZ-KD12NA4R1
General Information
Type
Concealed Duct
Product Line
M-Series
Product Category
Mini Split System Components
Operating Mode
Operating Mode
Some products are only capable of cooling, while others can either heat or cool a space. Some products heat via "heat pump" technology while others use electric heating elements. Learn More
Heating and Cooling
Multi-Zone Compatible
Yes
Refrigerant Type
R-410A
Indoor Unit Size(s)
Indoor Unit Size(s)
Mini split systems can have one or more indoor units connected to a single outdoor unit. Indoor Unit Size(s) specifies what indoor unit sizes are used in a system. We have combined 6k and 7k indoor units to enhance searchability.
12
Installation Location
Indoor
Performance
Cooling BTU
12000
Cooling Capacity
11500 BTU
Moisture Removal
2.4 Pints/Hour
Maximum Air Flow
388 CFM
Minimum Air Flow
247 CFM
Minimum Sound Level
23 dB
Maximum Sound Level
Maximum Sound Level
Sound levels are measured in decibels (dB). The lower the decibel rating, the less noise the product makes. As an example, a ticking watch is 20 dB while on the other end of the scale, a lawn mower is around 90 dB. Learn More
33 dB
Electrical Data
Phase
1
Frequency
60 Hz
Dimensions
Gas Connection Size
3/8 Inch
Liquid Connection Size
1/4 Inch
Product Height
7 7/8 Inches
Product Width
39 Inches
Product Depth
27 9/16 Inches
Product Weight
60 Pounds
Shipping Weight
70 Pounds
Certifications
ETL Listed
Yes
Warranty Information
Parts Warranty
Parts Warranty
A warranty is a safeguard from defects in manufacturing and can vary in length and terms. Some manufacturers require registration for extended warranty benefits, be sure to check out features and the warranty document. To see the manufacturer's warranty statement, click on the Manuals tab. Learn More
5 Years
Overview
Product Category
Mini Split System Components
MHK2
General Information
Type
Mini Split Controller
Product Line
RedLINK
Product Category
Mini Split Accessories
Programmable
Yes
Power Source
AA Batteries
Interface
Touchscreen
Performance
Minimum Operating Temperature
32 F
Maximum Operating Temperature
120 F
Dimensions
Product Height
4 1/12 Inches
Product Width
4 1/12 Inches
Product Depth
1 1/16 Inches
Overview
Product Category
Mini Split Accessories
Reviews
(3)
Mitsubishi M3H42D12121800-B Reviews & Ratings
Product Q&A
(2)
Product Questions
Answered by Ken, the eComfort Product Expert
Can these systems can be controlled by the Nest learning thermostat?
Jeff
from New York
February 15, 2017
When the room units are hung is it necessary to have holes through to the exterior of the house?
Kevin B.
from New York
August 07, 2016
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Manuals
MXZ-5C42NA4
SEZ-KD12NA4R1
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Mitsubishi Concealed Duct 3-Zone System - 42,000 BTU Outdoor - 12k + 12k + 18k Indoor - 15.2 SEER2
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