MXZ-SM42NLHZ-**
Mitsubishi Electric · HP - Mini or Multi Split
17–21.5BTU/Wh
11–11.1BTU/Wh
42000BTU/hr
Yes
Mitsubishi Electric MXZ-SM42NLHZ-**: SEER2 21.5 BTU/Wh, around the middle of the range for air-source heat pumps (category median 20 BTU/Wh).
SEER2: better than 86% of the 574 comparable models within 10% of this capacity. Their median is 16 BTU/Wh.
Where this model sits
The Mitsubishi Electric MXZ-SM42NLHZ-** is a 42000 BTU/hr hp - mini or multi split using R-454B, a refrigerant with moderate global warming potential (GWP 470). At 21.5 BTU/Wh it ranks around the middle of the 12,218 certified air-source heat pumps models. Among similar-sized air-source heat pumps (within 10% of its size), it is more efficient than the peer median of 16 BTU/Wh.
Specifications
| Efficiency | |
|---|---|
| SEER2 (best combination) | 21.5BTU/Wh |
| SEER2 (worst combination) | 17BTU/Wh |
| HSPF2 (best combination) | 11.1BTU/Wh |
| HSPF2 (worst combination) | 11BTU/Wh |
| EER2 (best combination) | 13.4BTU/Wh |
| COP at 5 °F | 2 |
| Capacity | |
| Cooling Capacity (max) | 42000BTU/hr |
| Cooling Capacity (min) | 42000BTU/hr |
| Heating at 47 °F | 48000BTU/hr |
| Heating at 17 °F | 34000BTU/hr |
| Heating at 5 °F | 48000BTU/hr |
All 25 specifications
| Configuration | |
|---|---|
| Product Type | HP - Mini or Multi Split |
| Compressor Staging | Continuously variable |
| Cold Climate Certified | Yes |
| Connected Capability | No |
| Series | Smart Multi |
| Indoor-Unit Combinations Rated | 3 |
| Refrigerant | |
| Type | R-454B |
| GWP Rating | R-454B (GWP:470 | Lower GWP) |
| Identifiers | |
| Model Number | MXZ-SM42NLHZ-** |
| ENERGY STAR ID | ES_14817_MXZ-SM42NLHZ-**_03262025010025_29217177371 |
| Partner | Mitsubishi Electric U.S. HVAC Division |
| Date Certified | 2026-04-17 |
| Available From | 2026-04-15 |
| Markets | United States |
Documentation
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