SplitAtlas

Mitsubishi Electric / M-Series GS

Mitsubishi M-Series GS 18k 230V Mini-Split

Certified capacity
18,000 BTU/h[1]
SEER2
21.5 SEER2[2]
Heating floor
-4 F[1]
Voltage
208/230V[1]
Install path
Professional install

The GS 18k is Mitsubishi's standard 1.5-ton single-zone: SEER2 21.5, HSPF2 10.3, with a substantial 21,600 BTU of heat at 47F, rated to -4F. It brings the M-Series efficiency and support to a large room, tuned for mild-to-moderate winters.

1 zoneProfessional installCurrent

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Error Codes
Mitsubishi Electric M-Series GS 18k mini-split heat pump indoor wall unit, outdoor condenser, and remote

Image: HVACDirect

Data completeness: 100%
Last sourced
Jul 20, 2026

SplitAtlas score

8.3 / 10

Methodology
Cooling efficiencyAbove average

(21.5 SEER2) among 18k systems

Heating efficiencyTop quartile

(10.3 HSPF2) among 18k systems

Cold-weather performanceBottom quartile

(17F rated capacity: 61.6% of the 47F rating; -4 F heating floor) among 18k systems

NoiseAbove average

(28 dBA indoor min / 55 dBA outdoor) among 18k systems

WarrantyTop quartile

(10 yr parts / 10 yr compressor) across the catalogue

Feature setBottom quartile

(1 verified feature) across the catalogue

Documentation & partsTop quartile

(6 manuals; spec sheet; parts channel) across the catalogue

Not evaluated

  • Installation accessibility — not applicable (professional install)N/A

    professional install - DIY-accessibility not applicable

  • Price-to-value — not evaluatedN/A

    This is a professionally installed, quote-only system, so we can't score its price. Get an installed quote to compare real cost.

    Get a quote

Key ratings

Rated cooling

18,000BTU/h[1]

Rated heating

21,600BTU/h[1]

Best-fit use cases

A large living room or open area in a mild-to-moderate climate where the buyer wants Mitsubishi support and high 1.5-ton heat output without sub-zero operation.

Buyer review snapshot

Install difficulty

Professional install
  • Electrical: 208/230V; MCA 12 A; breaker/fuse 15 A.
  • Line set: connection type not sourced; precharged 25 ft; max 100 ft.

Alternatives

Availability and price context

This system is sold through dealers, so its price comes as an installed quote that depends on your home. Get installation quotes to price it.

Source date

Model data sourced
Jul 20, 2026
Page reviewed
Jul 20, 2026
Source-backed records
3
Newest source retrieved
Jul 20, 2026

Warranty tiers

Base
5 yr parts / 7 yr compressor - licensed HVAC contractor installation
Registered
10 yr parts / 10 yr compressor - owner-occupied residence registered within 90 days of installation
Program
12 yr parts / 12 yr compressor - owner-occupied residence installed and registered by a Diamond Contractor within 90 days

The score uses Registered. Additional published terms are shown for reference and not counted in the score.

Review methodology

Model context

Install path
This is professional-install equipment; price it with an installed quote.

Strengths

  • 21,600 BTU of heat at 47F - strong output for a large space.
  • SEER2 21.5 / HSPF2 10.3 with Mitsubishi's dealer support and reliability reputation.

Weaknesses

  • Rated only to -4F - the GS 18k Hyper-Heat version is the cold-climate choice.

Climate suitability

Minimum heating ambient
-4 F[1]
Certified heating at 5F
not published
Maximum heating at 5F (manufacturer)
14,780 BTU/h[1]
Rated heating at 17F
13,300 BTU/h[1]
Rated heating at 47F
21,600 BTU/h[1]

Specifications

Show
Manufacturer
Mitsubishi Electric
Brand
Mitsubishi Electric
Product line
M-Series GS
Model number
MSZ-GS18NA-U1 indoor / MUZ-GS18NA-U1 outdoor
Indoor unit model
MSZ-GS18NA-U1
Outdoor unit model
MUZ-GS18NA-U1
Number of zones
1
Max indoor units
not published
Rated cooling capacity
18,000 BTU/h[1]
Rated heating capacity
21,600 BTU/h[1]
Voltage
208/230V[1]
MCA
12 A[1]
Maximum fuse or breaker size
15 A[1]
Breaker needed
not published
SEER2
21.5 SEER2[2]
EER2
13.45 EER2[2]
HSPF2 (Region 4)
10.3 HSPF2[2]
HSPF2 (Region 5)
not published
COP
not published
COP at 47F
3.77 COP[1]
COP at 5F
2.27 COP[1]
Minimum outdoor heating temperature
-4 F[1]
Minimum outdoor cooling temperature
14 F[1]
Maximum outdoor temperature
115 F[1]
Indoor noise range
cooling 28-33-38-44-49; heating 28-34-39-43-48[1]
Outdoor noise rating
55 dBA[1]
Indoor weight
28 lb[1]
Outdoor weight
119 lb[1]
Refrigerant
R-410A[1]
Refrigerant charge
55 oz[1]
Manufacturer coverage
not published
Line-set size
1/4 in liquid / 1/2 in suction
Included line-set length
Line set supplied by the installer
Maximum line-set length
100 ft[1]
Max line set per indoor
not published
Maximum elevation difference
50 ft[1]
Max height between indoor units
not published
Wi-Fi support
supported[1]
Energy Star status
ENERGY STAR certified[1]
AHRI certification number
207679245[2]
Warranty
Base: 5 yr parts / 7 yr compressor (licensed HVAC contractor installation); Registered: 10 yr parts / 10 yr compressor (owner-occupied residence registered within 90 days of installation); Program: 12 yr parts / 12 yr compressor (owner-occupied residence installed and registered by a Diamond Contractor within 90 days). Score uses Registered. Additional published terms are shown for reference and not counted in the score.. Standard residential M-Series warranty is 5 years parts and 7 years compressor from installation by a licensed HVAC contractor. Enhanced residential terms are 10 years parts and compressor for an owner-occupied residence registered within 90 days of installation, and 12 years parts and compressor when installed in an owner-occupied residence by a Diamond Contractor and registered by that Diamond Contractor within 90 days. The limited warranty statement itself requires licensed-contractor installation and does not state an Internet/resale purchase-channel condition.
Install path
Professional install
Retail price
Installed quote only
Available retailers
not published
Manual links
MUY(Z)-GS engineering data book, MSY(Z)-GS18NA installation manual, METUS Residential M-Series, P-Series and SMART MULTI Limited Warranty Statement, MSZ-GS indoor service manual, MUY(Z)-GS outdoor service manual, MSZ-GS18NA & MUZ-GS18NA submittal
Specification sheet
MSZ-GS18NA & MUZ-GS18NA submittal
Last sourced date
Jul 20, 2026

Parts and filters

Fits Mitsubishi Electric M-Series GS 18k 230V (MSZ-GS18NA / MUZ-GS18NA). Part numbers and fit notes identify compatibility only; no manufacturer endorsement is implied.

filter-anti-allergy

Mitsubishi anti-allergy enzyme filter

Fits
Mitsubishi Electric M-Series GS 18k 230V (MSZ-GS18NA / MUZ-GS18NA)
OEM part number
MAC-408FT-E
Filter care
Replace every year; vacuum every 3 months in between; if dirt remains, soak and rinse in lukewarm water, then shade-dry.
Fit note
Fits MSZ-GS18NA / MUZ-GS18NA. Manufacturer documentation publishes this OEM part number for this model family. No live HVACDirect exact-part offer was found. Amazon lists this exact OEM part, sold by My Filter Company.
Source
Mitsubishi Electric MSZ-GS18NA / MUZ-GS18NA Submittal, INDOOR UNIT ACCESSORIES: MSZ-GS18NA, page p. 4 (Filter Anti-allergy Enzyme Filter MAC-408FT-E)

Some retailer links may earn us a commission at no extra cost; paid relationships never change scores or recommendations. Affiliate disclosure

Paid link

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smart-controller-module

Mitsubishi Wireless Interface for kumo cloud

Fits
Mitsubishi Electric M-Series GS 18k 230V (MSZ-GS18NA / MUZ-GS18NA)
OEM part number
PAC-USWHS002-WF-2
Fit note
Fits MSZ-GS18NA / MUZ-GS18NA. Manufacturer documentation publishes this OEM part number for this model family. HVACDirect was verified as a live exact-part page on 2026-08-01.
Source
Mitsubishi Electric MSZ-GS18NA / MUZ-GS18NA Submittal, INDOOR UNIT ACCESSORIES: MSZ-GS18NA, page p. 4 (PAC-USWHS002-WF-2)

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Paid link

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control-interface

Mitsubishi M-Net and I/O Control Interface for M-Series

Fits
Mitsubishi Electric M-Series GS 18k 230V (MSZ-GS18NA / MUZ-GS18NA)
OEM part number
MAC-334IF-E
Fit note
Fits MSZ-GS18NA / MUZ-GS18NA. Manufacturer documentation publishes this OEM part number for this model family. HVACDirect was verified as a live exact-part page on 2026-08-01.
Source
Mitsubishi Electric MSZ-GS18NA / MUZ-GS18NA Submittal, INDOOR UNIT ACCESSORIES: MSZ-GS18NA, page p. 4 (M-Net & I/O Control Interface for M-Series MAC-334IF-E)

Some retailer links may earn us a commission at no extra cost; paid relationships never change scores or recommendations. Affiliate disclosure

Paid link

Check price at HVACDirect

wireless-remote-controller

Mitsubishi kumo touch RedLINK wireless controller

Fits
Mitsubishi Electric M-Series GS 18k 230V (MSZ-GS18NA / MUZ-GS18NA)
OEM part number
MHK2
Fit note
Fits MSZ-GS18NA / MUZ-GS18NA. Manufacturer documentation publishes this OEM part number for this model family. HVACDirect was verified as a live exact-part page on 2026-08-01.
Source
Mitsubishi Electric MSZ-GS18NA / MUZ-GS18NA Submittal, INDOOR UNIT ACCESSORIES: MSZ-GS18NA, page p. 4 (kumo touch™ RedLINK™ Wireless Controller & Receiver kit MHK2)

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Paid link

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Find this model's filterReplacement Parts & Filters

Electrical requirements

Show
Voltage
not published
Voltage range
208/230V[1]
Phase
1[1]
Frequency
60 Hz[1]
MCA
12 A[1]
Breaker needed
not published
Maximum breaker size
not published
Maximum fuse size
15 A[1]
Maximum cooling current
not published
Maximum heating current
not published
Manufacturer wire notes
14 AWG indoor-outdoor[1]

Installation considerations

Show
Liquid line
1/4 in[1]
Suction line
1/2 in[1]
Line connection type
not published
Precharged length
25 ft[1]
Included line-set length
Line set supplied by the installer
Maximum line-set length
100 ft[1]
Max line set per indoor
not published
Max height between indoor units
not published
Indoor dimensions
36-5/16 x 9-13/16 x 12 in[1]
Outdoor dimensions
33-1/16 x 13 x 34-5/8 in[1]
Indoor weight
28 lb[1]
Outdoor weight
119 lb[1]
Drain size
5/8 in[1]

Related systems and guides

Frequently asked questions

Can I install the Mitsubishi Electric M-Series GS 18k 230V (MSZ-GS18NA / MUZ-GS18NA) myself, or do I need a pro?
Mitsubishi Electric M-Series GS 18k 230V (MSZ-GS18NA / MUZ-GS18NA) is built for professional installation: the line set must be flared, evacuated, and charged, which requires EPA-certified refrigerant handling. Installing it outside the manufacturer's requirements can void the warranty, so budget for a qualified HVAC installer.
Will the Mitsubishi Electric M-Series GS 18k 230V (MSZ-GS18NA / MUZ-GS18NA) keep heating in a cold winter?
Rated heating operation extends down to -4 F. Certified heating efficiency is 10.3 HSPF2. Match that published heating floor against your climate's design temperature - below the low-ambient rating, output can fall off or the system can pause to protect itself.
What electrical circuit does the Mitsubishi Electric M-Series GS 18k 230V (MSZ-GS18NA / MUZ-GS18NA) need?
Published electrical requirements: 208/230V voltage, 12 A minimum circuit ampacity, and 15 A maximum breaker or fuse sizing. Confirm the final circuit against the unit nameplate and local code with a licensed electrician.
How far can the outdoor unit be from the indoor head?
The published maximum line-set length is 100 ft. The outdoor unit's factory charge covers up to 25 ft of line; longer runs need added refrigerant. Measure the planned routing before ordering.
What warranty does the Mitsubishi Electric M-Series GS 18k 230V (MSZ-GS18NA / MUZ-GS18NA) carry?
The manufacturer publishes these warranty tiers: Base: 5 yr parts / 7 yr compressor (licensed HVAC contractor installation); Registered: 10 yr parts / 10 yr compressor (owner-occupied residence registered within 90 days of installation); Program: 12 yr parts / 12 yr compressor (owner-occupied residence installed and registered by a Diamond Contractor within 90 days). Score uses Registered. Additional published terms are shown for reference and not counted in the score.. Registration requirements and proof of qualified installation commonly affect coverage, so read the warranty terms before install day.

Data sources

Show
  1. Mitsubishi Electric Trane HVAC US: MSZ-GS18NA & MUZ-GS18NA submittalSourced - manufacturer technical document

    Covers Frequency, electrical_spec.guaranteed_voltage_range, electrical_spec.indoor_mca_amps, Maximum fuse size, Minimum circuit ampacity, Phase and more

  2. AHRI: AHRI Directory Air-Source Heat Pumps record ref 207679245Sourced - AHRI directory

    Covers AHRI certification number, performance_spec.cold_climate_designation, EER2, HSPF2 (Region 4), SEER2

  3. Mitsubishi Electric Trane HVAC US LLC: METUS Residential M-Series, P-Series and SMART MULTI Limited Warranty StatementSourced - secondary source

    Covers Additional published compressor warranty, Additional published warranty conditions, Additional published parts warranty, Legacy compressor warranty value, Legacy warranty value, Registered compressor warranty and more

Last updated

Jul 20, 2026