42,000 BTU mini-split heat pump · P-Series
Trane / Mitsubishi Electric PUZ-A42NKA7
Below average cooling and heating efficiency for a 42,000 BTU mini-split heat pump, but not rated for cold climates.
Ranks #30 of 61 42,000 BTU mini-splits for cooling efficiency, and costs about $1,229 a year to run in a mixed climate like Atlanta.
- SEER2
- 21.5 Cooling efficiency over a seasonBelow average · beats 39%
- HSPF2
- 9.4 Heating efficiency over a seasonBelow average · beats 19%
- EER2
- 11.6 Cooling efficiency on a 95°F dayBelow average · beats 14%
- Heat at 5°F
- 20,000 BTU/h42% of its 47°F outputAverage · beats 60%
A good fit if…
- You want steady temperatures and quiet running - the compressor varies its speed.
Think twice if…
- You often see nights below 0°F - it is not cold-climate certified.
- Cooling cost matters most - its SEER2 is below average for mini-splits.
- You mainly need heat - its HSPF2 is below average for mini-splits.
- You want the newest refrigerant - it uses R-410A, which is being phased down.
Details
Specifications
| General | |
|---|---|
| Brand | Trane / Mitsubishi Electric |
| Also sold as | Mitsubishi Electric |
| Outdoor unit model | PUZ-A42NKA7 |
| Series | P-Series |
| Type | Mini-split heat pump |
| Nominal size | 42,000 BTU |
| CompressorVariable-speed units run longer at low power | Continuously variable |
| Refrigerant | R-410A |
| Connected (smart) capable | No |
| On the market since | December 1, 2022 |
| Last certified | October 17, 2025 |
| Cooling | |
| SEER2Seasonal efficiency, higher is better | 21.5 (range 21.5) |
| EER2Efficiency at 95°F outdoors | 11.6 |
| Cooling capacity | 42,000 BTU/h |
| Heating | |
| HSPF2Seasonal efficiency, higher is better | 9.4 |
| Capacity at 47°F | 48,000 BTU/h |
| Capacity at 17°F | 28,000 BTU/h |
| Capacity at 5°F | 20,000 BTU/h |
| COP at 5°F2.0 = twice as efficient as a space heater | 2.05 |
| ENERGY STAR cold climate | No |
Heating output as it gets colder
Every heat pump delivers less heat as the outdoor temperature drops. Certified output of its matchup with TPLA0A0421EA70 at the standard test temperatures, in BTU/h:
Certified matchups
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. |
|---|---|---|---|---|---|
| TPLA0A0421EA70 | 21.5 | 11.6 | 9.4 | 20,000 | 206720361 |
| PLA-A42EA Mitsubishi Electric | 21.5 | 11.6 | 9.4 | 20,000 | 201754482 |
Same unit, other model numbers
These model numbers have exactly the same certified ratings and matchups as the Trane / Mitsubishi Electric PUZ-A42NKA7: the same equipment under another brand, or a variant code for voltage, colour or market. Everything on this page applies to them.
- Trane / Mitsubishi Electric TRUZA0421KA70
Yearly running cost in 10 large cities
- Phoenix, AZ$1,226/yr
- Miami, FL$927/yr
- Houston, TX$1,102/yr
- Atlanta, GA$1,229/yr
- Los Angeles, CA$1,222/yr
- New York, NY$3,078/yr
- Chicago, IL$2,526/yr
- Denver, CO$2,122/yr
- Seattle, WA$1,321/yr
- Minneapolis, MN$2,635/yr
At each state's average electricity price and the city's typical heating and cooling hours.
Questions
- What is the SEER2 rating of the Trane / Mitsubishi Electric PUZ-A42NKA7?
- The Trane / Mitsubishi Electric PUZ-A42NKA7 is rated at up to 21.5 SEER2 and 11.6 EER2 for cooling and up to 9.4 HSPF2 for heating. The exact figure depends on the indoor unit it is paired with.
- Is the Trane / Mitsubishi Electric PUZ-A42NKA7 good for cold climates?
- It is not cold-climate certified: none of its matchups meet the ENERGY STAR cold-climate criteria (a COP of at least 1.75 at 5°F among other limits). In places with frequent sub-zero nights, pick a cold-climate 42,000 BTU model.
- How much does the Trane / Mitsubishi Electric PUZ-A42NKA7 cost to run per year?
- At its rated efficiency it costs about $927-$3,078 a year in electricity in large U.S. cities, depending on climate and local rates - for example $1,226 in Phoenix and $2,635 in Minneapolis. The calculator on this page works it out for your city and compares it with your current system.
- Is the Trane / Mitsubishi Electric PUZ-A42NKA7 the same as the Trane / Mitsubishi Electric TRUZA0421KA70?
- 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 Trane / Mitsubishi Electric PUZ-A42NKA7?
- ENERGY STAR lists 2 certified combinations for this outdoor unit. The highest-rated ones use TPLA0A0421EA70, Mitsubishi Electric PLA-A42EA.
- What refrigerant does the Trane / Mitsubishi Electric PUZ-A42NKA7 use?
- It uses R-410A. R-410A is being phased down under the EPA AIM Act, and new systems are moving to R-454B and R-32.
Running cost and savings
Pre-filled with this model. Pick your city and what you heat with today; everything else is optional.
Similar 42,000 BTU models
- LG KUSXA421A · cold climate21.5 SEER2 · 10.8 HSPF2
- AproDr AM6OG-48HFN1 · cold climate21.3 SEER2 · 10.6 HSPF2
- LG KUMXA421A · cold climate21.5 SEER2 · 11.0 HSPF2
- Panasonic CU - 6YM48CBUC · cold climate21.3 SEER2 · 10.6 HSPF2
- Mitsubishi Electric MXZ-SM42NLHZ · cold climate21.5 SEER2 · 11.1 HSPF2
- LG KUSXB421A · cold climate21.0 SEER2 · 10.8 HSPF2
- Mitsubishi Electric MXZ-SM42NAMHZ2 · cold climate21.5 SEER2 · 11.1 HSPF2
- Mitsubishi Electric PUZ-AK42NL21.0 SEER2 · 10.1 HSPF2
See all 61 42,000 BTU mini-splits, ranked
Source: ENERGY STAR Certified Heat Pumps (U.S. EPA), certification of October 17, 2025. How we use the data.