Lennox / AIR-SOURCE HEAT PUMP

MLB012S4S-1P

M series

12 published source records · source checked Sep 21, 2026

SEER2 range19.5–25.5BTU/Wh
HSPF2 range10–10.4BTU/Wh
Cooling capacity11,800–12,000BTU/h

Each efficiency range summarizes published EPA records for MLB012S4S-1P. The highest SEER2 and HSPF2 may belong to different combinations. Open a source record below to see its ratings and the scope of its component information.

Model patterns and component strings are preserved exactly. How to read model patterns and combinations →

Heating performance & equipment details

Ranges include the 12 published source records for this model. Values in different rows may describe different configurations. Open an individual record to compare values from the same test configuration.

Reported fieldValue / rangeRecords supplying it
SEER2 · BTU/Wh19.5–25.512 / 12
EER2 · BTU/Wh11.7–13.512 / 12
HSPF2 · BTU/Wh10–10.412 / 12
Cooling capacity · BTU/h11,800–12,00012 / 12
Heating capacity at 47°F / 8.3°C · BTU/h12,000–12,50012 / 12
Heating capacity at 17°F / −8.3°C · BTU/h9,600–10,60012 / 12
Heating capacity at 5°F / −15°C · BTU/h11,300–12,10012 / 12
COP at 5°F / −15°C1.8–1.9612 / 12
Equipment / loop typeHP - Mini or Multi Split12 / 12
Refrigerant / source-reported GWPR-410A (GWP:2088)12 / 12
Compressor stagingContinuously variable12 / 12
Connected capabilityNo12 / 12

47°F = 8.3°C; 17°F = −8.3°C; 5°F = −15°C. COP is dimensionless. These are reported rating points, not a prediction of a particular home’s heat demand or operating limit.

Matched systems

Each row is one source record. The component column distinguishes listed combinations from outdoor-model ratings without an indoor configuration.

Indoor unit / required furnaceSEER2BTU/WhHSPF2BTU/WhHeating capacity at 5°F / −15°CBTU/hCOP at 5°F / −15°CRecord & comparison
MWMC012S4*Cold climate designationAHRI reference: 21066562825.5010.40120001.80EPA 2469753
MWMC012S4-1PCold climate designationAHRI reference: 20768352125.5010.40120001.80EPA 2469771
MWMC012S4-*PCold climate designationAHRI reference: 21103444125.5010.40120001.80EPA 2470607
MFMA012S4-1PCold climate designationAHRI reference: 20768352823.6010.00120001.89EPA 2469774
MFMA012S4-*PCold climate designationAHRI reference: 21103445023.6010.00120001.89EPA 2470595
MFMA012S4*Cold climate designationAHRI reference: 21066563723.6010.00120001.89EPA 2470615
M22A012S4-2PCold climate designationAHRI reference: 20768353222.3010.20113001.89EPA 2469764
M22A012S4-*PCold climate designationAHRI reference: 21103445622.3010.20113001.89EPA 2470488
M22A012S4*Cold climate designationAHRI reference: 21066564322.3010.20113001.89EPA 2470614
MMDB012S4-2PCold climate designationAHRI reference: 20768352519.5010.00121001.96EPA 2469775
MMDB012S4-*PCold climate designationAHRI reference: 21103444519.5010.00121001.96EPA 2470601
MMDB012S4*Cold climate designationAHRI reference: 21066563219.5010.00121001.96EPA 2470608

Sources and documentation

The table uses public EPA ENERGY STAR data. AHRI references are reported by EPA and have not been independently checked with AHRI. Source records do not establish availability, installation suitability or rebate eligibility.

No manufacturer manual has been matched to this model.

Collection method, revision history and known limitations →