Lennox MLB018S4M-1PvsWEATHERMAKER PH5SAN518**AA*
Side-by-side heat pump comparison
Lennox MLB018S4M-1P
SEER2
19–21.7BTU/Wh
HSPF2
9.3–9.8BTU/Wh
Cooling Capacity
19000BTU/hr
Cold Climate
Yes
Cold climate certified
WEATHERMAKER PH5SAN518**AA*
SEER2
15.2–15.5BTU/Wh
HSPF2
7.8–8BTU/Wh
Cooling Capacity
17400–18900BTU/hr
Refrigerant
R-454B
GWP 470 · Lower
Key differences
Lennox MLB018S4M-1P is 29% more efficient at 21.7 BTU/Wh versus 15.5 BTU/Wh for the WEATHERMAKER PH5SAN518**AA*. The Lennox MLB018S4M-1P is larger at 19000 BTU/hr versus 18900 BTU/hr. WEATHERMAKER PH5SAN518**AA* uses a lower-impact refrigerant: R-454B (GWP 470) versus R-410A (GWP 2088). Overall, the Lennox MLB018S4M-1P sits higher in the category, ranking above 37% of certified air-source heat pumps.
Efficiency
| Spec | Lennox | WEATHERMAKER |
|---|---|---|
| SEER2 (best combination)(BTU/Wh) | 21.7 | 15.5 |
| SEER2 (worst combination)(BTU/Wh) | 19 | 15.2 |
| HSPF2 (best combination)(BTU/Wh) | 9.8 | 8 |
| HSPF2 (worst combination)(BTU/Wh) | 9.3 | 7.8 |
| EER2 (best combination)(BTU/Wh) | 12.5 | 12.5 |
| COP at 5 °F | 1.90 | 2.10 |
Capacity
| Spec | Lennox | WEATHERMAKER |
|---|---|---|
| Cooling Capacity (max)(BTU/hr) | 19000 | 18900 |
| Cooling Capacity (min)(BTU/hr) | 19000 | 17400 |
| Heating at 47 °F(BTU/hr) | 20000 | 18300 |
| Heating at 17 °F(BTU/hr) | 16000 | 11000 |
| Heating at 5 °F(BTU/hr) | 19700 | 8600 |
Configuration
| Spec | Lennox | WEATHERMAKER |
|---|---|---|
| Product Type | HP - Mini or Multi Split | HP - Split System |
| Compressor Staging | Continuously variable | Single stage |
| Cold Climate Certified | Yes | No |
| Connected Capability | No | No |
| Series | M series | 15 SEER2 HP |
| Indoor-Unit Combinations Rated | 3 | 38 |
Refrigerant
| Spec | Lennox | WEATHERMAKER |
|---|---|---|
| Type | R-410A | R-454B |
| GWP Rating | R-410A (GWP:2088) | R-454B (GWP:470 | Lower GWP) |