Thermal Zone TZP15AZ18AJ2NvsWillis MZUHW18KCH21S2-O
Side-by-side heat pump comparison
Thermal Zone TZP15AZ18AJ2N
SEER2
15.2BTU/Wh
HSPF2
7.8–8.1BTU/Wh
Cooling Capacity
17100BTU/hr
Cold Climate
Yes
Cold climate certified
Willis MZUHW18KCH21S2-O
SEER2
21BTU/Wh
HSPF2
10BTU/Wh
Cooling Capacity
17000BTU/hr
Cold Climate
Yes
Cold climate certified
Key differences
Willis MZUHW18KCH21S2-O is 28% more efficient at 21.0 BTU/Wh versus 15.2 BTU/Wh for the Thermal Zone TZP15AZ18AJ2N. The Thermal Zone TZP15AZ18AJ2N is larger at 17100 BTU/hr versus 17000 BTU/hr. Overall, the Willis MZUHW18KCH21S2-O sits higher in the category, ranking above 24% of certified air-source heat pumps.
Efficiency
| Spec | Thermal Zone | Willis |
|---|---|---|
| SEER2 (best combination)(BTU/Wh) | 15.2 | 21 |
| SEER2 (worst combination)(BTU/Wh) | 15.2 | 21 |
| HSPF2 (best combination)(BTU/Wh) | 8.1 | 10 |
| HSPF2 (worst combination)(BTU/Wh) | 7.8 | 10 |
| EER2 (best combination)(BTU/Wh) | 11.7 | 12 |
| COP at 5 °F | 2.10 | 2.22 |
Capacity
| Spec | Thermal Zone | Willis |
|---|---|---|
| Cooling Capacity (max)(BTU/hr) | 17100 | 17000 |
| Cooling Capacity (min)(BTU/hr) | 17100 | 17000 |
| Heating at 47 °F(BTU/hr) | 17100 | 18000 |
| Heating at 17 °F(BTU/hr) | 12000 | 15000 |
| Heating at 5 °F(BTU/hr) | 9400 | 13600 |
Configuration
| Spec | Thermal Zone | Willis |
|---|---|---|
| Product Type | HP - Split System | HP - Mini or Multi Split |
| Compressor Staging | Two-stage | Continuously variable |
| Cold Climate Certified | Yes | Yes |
| Connected Capability | No | No |
| Series | Value | MultiHeat |
| Indoor-Unit Combinations Rated | 6 | 1 |
Refrigerant
| Spec | Thermal Zone | Willis |
|---|---|---|
| Type | R-410A | R-410A |
| GWP Rating | R-410A (GWP:2088) | R-410A (GWP:2088) |