What is the SEER2 rating of the Lennox MMLD036S6M-1P?

The Lennox MMLD036S6M-1P is rated at up to 21.5 SEER2 and 12.5 EER2 for cooling and up to 9.5 HSPF2 for heating. The exact figure depends on the indoor unit it is paired with; across its 3 certified matchups SEER2 ranges from 18.5-21.5.

Is the Lennox MMLD036S6M-1P good for cold climates?

Yes. At least one certified matchup meets the ENERGY STAR cold-climate criteria, delivering up to 36,600 BTU/h at 5°F with a COP of 2.04, so it is still 2.0 times as efficient as electric resistance heat at that temperature.

How much does the Lennox MMLD036S6M-1P cost to run per year?

At its rated efficiency it costs about $748-$2,294 a year in electricity in large U.S. cities, depending on climate and local rates - for example $963 in Phoenix and $1,948 in Minneapolis. The calculator on this page works it out for your city and compares it with your current system.

Is the Lennox MMLD036S6M-1P the same as the Samsung AJ036DXS4CG?

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.

36,000 BTU mini-split heat pump · MMLD Multi-Zone

Lennox MMLD036S6M-1P

Below average cooling and heating efficiency for a 36,000 BTU mini-split heat pump, and certified for cold climates.

Ranks #96 of 205 36,000 BTU mini-splits for cooling efficiency, and costs about $931 a year to run in a mixed climate like Atlanta.

SEER2: 21.5 Cooling efficiency over a season
Below average · beats 39%
HSPF2: 9.5 Heating efficiency over a season
Below average · beats 24%
EER2: 12.5 Cooling efficiency on a 95°F day
Average · beats 44%
Heat at 5°F: 36,600 BTU/h100% of its 47°F output
Average · beats 59%

A good fit if…

Your winters get properly cold - it is ENERGY STAR cold-climate certified, with 36,600 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.
You mainly need heat - its HSPF2 is below average for mini-splits.

Calculate my running cost

Details

Specifications36,000 BTU, R-32

General
Brand	Lennox
Also sold as	Samsung
Outdoor unit model	MMLD036S6M-1P
Series	MMLD Multi-Zone
Type	Mini-split heat pump
Nominal size	36,000 BTU
CompressorVariable-speed units run longer at low power	Continuously variable
Refrigerant	R-32
Connected (smart) capable	No
On the market since	January 1, 2025
Last certified	April 17, 2026
Cooling
SEER2Seasonal efficiency, higher is better	21.5 (range 18.5-21.5)
EER2Efficiency at 95°F outdoors	11.7-12.5
Cooling capacity	34,000 BTU/h
Heating
HSPF2Seasonal efficiency, higher is better	8.5-9.5
Capacity at 47°F	34,600-36,600 BTU/h
Capacity at 17°F	20,600-23,000 BTU/h
Capacity at 5°F	34,600-36,600 BTU/h
COP at 5°F2.0 = twice as efficient as a space heater	1.81-2.04
ENERGY STAR cold climate	Yes

Heating output as it gets colder100% kept at 5°F

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

Certified matchups3 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.
- LENNOX · cold climate	21.5	12.5	9.5	36,600	216760275
- LENNOX · cold climate	20.0	12.1	9.0	35,600	216760283
- LENNOX · cold climate	18.5	11.7	8.5	34,600	216760279

Same unit, other model numbers1

These model numbers have exactly the same certified ratings and matchups as the Lennox MMLD036S6M-1P: the same equipment under another brand, or a variant code for voltage, colour or market. Everything on this page applies to them.

Samsung AJ036DXS4CG

Yearly running cost in 10 large cities$748-$2,294

Phoenix, AZ$963/yr
Miami, FL$748/yr
Houston, TX$864/yr
Atlanta, GA$931/yr
Los Angeles, CA$919/yr
New York, NY$2,294/yr
Chicago, IL$1,876/yr
Denver, CO$1,570/yr
Seattle, WA$973/yr
Minneapolis, MN$1,948/yr

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

Questions5

What is the SEER2 rating of the Lennox MMLD036S6M-1P?: The Lennox MMLD036S6M-1P is rated at up to 21.5 SEER2 and 12.5 EER2 for cooling and up to 9.5 HSPF2 for heating. The exact figure depends on the indoor unit it is paired with; across its 3 certified matchups SEER2 ranges from 18.5-21.5.
Is the Lennox MMLD036S6M-1P good for cold climates?: Yes. At least one certified matchup meets the ENERGY STAR cold-climate criteria, delivering up to 36,600 BTU/h at 5°F with a COP of 2.04, so it is still 2.0 times as efficient as electric resistance heat at that temperature.
How much does the Lennox MMLD036S6M-1P cost to run per year?: At its rated efficiency it costs about $748-$2,294 a year in electricity in large U.S. cities, depending on climate and local rates - for example $963 in Phoenix and $1,948 in Minneapolis. The calculator on this page works it out for your city and compares it with your current system.
Is the Lennox MMLD036S6M-1P the same as the Samsung AJ036DXS4CG?: 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.
What refrigerant does the Lennox MMLD036S6M-1P use?: It uses R-32.

Running cost and savings

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

Heat pump $976/yrYou save $803/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 Lennox MMLD036S6M-1P

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: $976
Current system, per year: $1,779
You save per year: $803
Payback: 16.2 years
Net after 10 years: -$4,971

Cooling $557Heating $420Electricity used: 6,102 kWhSaved vs. a minimum-efficiency heat pump: $392

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 36,000 BTU models

ZERO Z4SOV-36HDMB-USHH · cold climate21.5 SEER2 · 11.3 HSPF2
Arcoaire D5CLHAH36AAK · cold climate21.3 SEER2 · 11.1 HSPF2
Fujitsu AOUK036SSAN7 · cold climate21.7 SEER2 · 10.8 HSPF2
Carrier 37MBHAQ36AA3 · cold climate21.3 SEER2 · 11.1 HSPF2
Mitsubishi Electric PUZ-A36NKA822.0 SEER2 · 9.3 HSPF2
MDV MOX630-36HFN10-M2X · cold climate21.3 SEER2 · 11.1 HSPF2
Mitsubishi Electric PUZ-A36NKA722.0 SEER2 · 9.3 HSPF2
Fujitsu AOUH36KUAS1 · cold climate21.3 SEER2 · 10.5 HSPF2

See all 205 36,000 BTU mini-splits, ranked

Source: ENERGY STAR Certified Heat Pumps (U.S. EPA), certification of April 17, 2026. How we use the data.