What is the SEER2 rating of the Mitsubishi Electric MUZ-GX24NL?

The Mitsubishi Electric MUZ-GX24NL is rated at up to 21.5 SEER2 and 13.0 EER2 for cooling and up to 10.3 HSPF2 for heating. The exact figure depends on the indoor unit it is paired with.

Is the Mitsubishi Electric MUZ-GX24NL good for cold climates?

Yes. At least one certified matchup meets the ENERGY STAR cold-climate criteria, delivering up to 19,400 BTU/h at 5°F with a COP of 1.80, so it is still 1.8 times as efficient as electric resistance heat at that temperature.

How much does the Mitsubishi Electric MUZ-GX24NL cost to run per year?

At its rated efficiency it costs about $494-$1,619 a year in electricity in large U.S. cities, depending on climate and local rates - for example $651 in Phoenix and $1,384 in Minneapolis. The calculator on this page works it out for your city and compares it with your current system.

Is the Mitsubishi Electric MUZ-GX24NL the same as the Mitsubishi Electric MUZ-GX24NLH2?

Yes, as far as the certified ratings go. ENERGY STAR lists both model numbers with identical efficiency, capacity and matchups, which means the same outdoor unit sold under a different brand or with a minor variant code (voltage, colour or region). The full list is on this page.

Which indoor units work with the Mitsubishi Electric MUZ-GX24NL?

ENERGY STAR lists 1 certified combination for this outdoor unit. The highest-rated one uses MSZ-GX24NL.

24,000 BTU mini-split heat pump · M-Series

Mitsubishi Electric MUZ-GX24NL

Below average cooling efficiency and average heating efficiency for a 24,000 BTU mini-split heat pump, and certified for cold climates.

Ranks #245 of 430 24,000 BTU mini-splits for cooling efficiency, and costs about $648 a year to run in a mixed climate like Atlanta.

SEER2: 21.5 Cooling efficiency over a season
Below average · beats 39%
HSPF2: 10.3 Heating efficiency over a season
Average · beats 55%
EER2: 13.0 Cooling efficiency on a 95°F day
Average · beats 62%
Heat at 5°F: 19,400 BTU/h70% of its 47°F output
Below average · beats 9%

A good fit if…

Your winters get properly cold - it is ENERGY STAR cold-climate certified, with 19,400 BTU/h at 5°F.
You want steady temperatures and quiet running - the compressor varies its speed.

Think twice if…

Cooling cost matters most - its SEER2 is below average for mini-splits.

Calculate my running cost

Details

Specifications24,000 BTU, R-454B

General
Brand	Mitsubishi Electric
Outdoor unit model	MUZ-GX24NL
Series	M-Series
Type	Mini-split heat pump
Nominal size	24,000 BTU
CompressorVariable-speed units run longer at low power	Continuously variable
Refrigerant	R-454B
Connected (smart) capable	No
On the market since	January 1, 2025
Last certified	February 17, 2025
Cooling
SEER2Seasonal efficiency, higher is better	21.5 (range 21.5)
EER2Efficiency at 95°F outdoors	13.0
Cooling capacity	22,400 BTU/h
Heating
HSPF2Seasonal efficiency, higher is better	10.3
Capacity at 47°F	27,600 BTU/h
Capacity at 17°F	19,200 BTU/h
Capacity at 5°F	19,400 BTU/h
COP at 5°F2.0 = twice as efficient as a space heater	1.80
ENERGY STAR cold climate	Yes

Heating output as it gets colder70% kept at 5°F

Every heat pump delivers less heat as the outdoor temperature drops. Certified output of its matchup with MSZ-GX24NL at the standard test temperatures, in BTU/h:

Certified matchups1 indoor units

The same outdoor unit scores differently with each indoor unit. Ask your installer for the AHRI reference number of the exact system you are quoted.

Indoor unit	SEER2	EER2	HSPF2	Heat @5°F	AHRI ref.
MSZ-GX24NL · cold climate	21.5	13.0	10.3	19,400	215862737

Same unit, other model numbers1

These model numbers have exactly the same certified ratings and matchups as the Mitsubishi Electric MUZ-GX24NL: the same equipment under another brand, or a variant code for voltage, colour or market. Everything on this page applies to them.

Mitsubishi Electric MUZ-GX24NLH2

Yearly running cost in 10 large cities$494-$1,619

Phoenix, AZ$651/yr
Miami, FL$494/yr
Houston, TX$585/yr
Atlanta, GA$648/yr
Los Angeles, CA$644/yr
New York, NY$1,619/yr
Chicago, IL$1,328/yr
Denver, CO$1,115/yr
Seattle, WA$694/yr
Minneapolis, MN$1,384/yr

At each state's average electricity price and the city's typical heating and cooling hours.

Questions6

What is the SEER2 rating of the Mitsubishi Electric MUZ-GX24NL?: The Mitsubishi Electric MUZ-GX24NL is rated at up to 21.5 SEER2 and 13.0 EER2 for cooling and up to 10.3 HSPF2 for heating. The exact figure depends on the indoor unit it is paired with.
Is the Mitsubishi Electric MUZ-GX24NL good for cold climates?: Yes. At least one certified matchup meets the ENERGY STAR cold-climate criteria, delivering up to 19,400 BTU/h at 5°F with a COP of 1.80, so it is still 1.8 times as efficient as electric resistance heat at that temperature.
How much does the Mitsubishi Electric MUZ-GX24NL cost to run per year?: At its rated efficiency it costs about $494-$1,619 a year in electricity in large U.S. cities, depending on climate and local rates - for example $651 in Phoenix and $1,384 in Minneapolis. The calculator on this page works it out for your city and compares it with your current system.
Is the Mitsubishi Electric MUZ-GX24NL the same as the Mitsubishi Electric MUZ-GX24NLH2?: Yes, as far as the certified ratings go. ENERGY STAR lists both model numbers with identical efficiency, capacity and matchups, which means the same outdoor unit sold under a different brand or with a minor variant code (voltage, colour or region). The full list is on this page.
Which indoor units work with the Mitsubishi Electric MUZ-GX24NL?: ENERGY STAR lists 1 certified combination for this outdoor unit. The highest-rated one uses MSZ-GX24NL.
What refrigerant does the Mitsubishi Electric MUZ-GX24NL use?: It uses R-454B.

Running cost and savings

Pre-filled with this model. Pick your city and what you heat with today; everything else is optional.

Heat pump $667/yrYou save $573/yrSee details ↓

1. Where you live

StateCityElectricity ¢ per kWh

Adjust heating and cooling hours

Filled in from your city's climate. Change them if you run the system much more or less than usual.

Cooling hours full-load hours per yearHeating hours full-load hours per year

2. The heat pump Mitsubishi Electric MUZ-GX24NL

Find a model (fills in the ratings below)

SEER2 cooling efficiencyHSPF2 heating efficiencyCooling capacity BTU/hHeating capacity BTU/h

3. What it replaces

Current heatingFurnace efficiency (AFUE %)Gas price, $/thermCurrent coolingOld AC rating SEER2 (10 ≈ 15+ years old)

4. Price replace the example with your quote

Installed price, $Rebates and incentives, $ utility, state

Heat pump, per year: $667
Current system, per year: $1,240
You save per year: $573
Payback: 14.8 years
Net after 10 years: -$2,768

Cooling $367Heating $300Electricity used: 4,168 kWhSaved vs. a minimum-efficiency heat pump: $297

Estimates use the unit's rated SEER2 and HSPF2, full-load hours derived from NOAA 1991-2020 degree days, average residential electricity prices from the U.S. EIA (12 months to July 2026) and fuel prices from EIA (2025 for natural gas, week of 2026-10-05 for propane and heating oil). Very cold days that need backup heat are not modelled. Federal minimum for comparison: 14.3 SEER2 / 7.5 HSPF2.

Similar 24,000 BTU models

TGM MRSVHT24AS · cold climate21.5 SEER2 · 11.2 HSPF2
Fujitsu AOUH24KPAS1 · cold climate21.5 SEER2 · 10.0 HSPF2
SLIMAIR SHC24VE2AG · cold climate21.5 SEER2 · 11.2 HSPF2
Sea Breeze SZ24H424ZMO · cold climate21.5 SEER2 · 11.2 HSPF2
Star Air Kontrol SAK-24-CC/220V · cold climate21.5 SEER2 · 9.7 HSPF2
Lennox LISH024000P431-D · cold climate21.5 SEER2 · 11.2 HSPF2
ACD UHD24KCH22S-O · cold climate21.5 SEER2 · 9.5 HSPF2
LBG Products LBHB24DUWO · cold climate21.5 SEER2 · 11.2 HSPF2

See all 430 24,000 BTU mini-splits, ranked

Source: ENERGY STAR Certified Heat Pumps (U.S. EPA), certification of February 17, 2025. How we use the data.