CHW12KCH18S2-O
Willis · HP - Mini or Multi Split
17.5BTU/Wh
8.5BTU/Wh
12000BTU/hr
Yes
Willis CHW12KCH18S2-O: SEER2 17.5 BTU/Wh, around the middle of the range for air-source heat pumps (category median 20 BTU/Wh).
SEER2: worse than 94% of the 1144 comparable models within 10% of this capacity. Their median is 23.5 BTU/Wh.
Where this model sits
The Willis CHW12KCH18S2-O is a 12000 BTU/hr hp - mini or multi split using R-410A, a refrigerant with high global warming potential (GWP 2088). At 17.5 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 less efficient than the peer median of 23.5 BTU/Wh. In this size range, comparable GREE models average 24.3 BTU/Wh and Hisense models average 23 BTU/Wh.
Specifications
| Efficiency | |
|---|---|
| SEER2 (best combination) | 17.5BTU/Wh |
| SEER2 (worst combination) | 17.5BTU/Wh |
| HSPF2 (best combination) | 8.5BTU/Wh |
| HSPF2 (worst combination) | 8.5BTU/Wh |
| EER2 (best combination) | 8.7BTU/Wh |
| COP at 5 °F | 1.80 |
| Capacity | |
| Cooling Capacity (max) | 12000BTU/hr |
| Cooling Capacity (min) | 12000BTU/hr |
| Heating at 47 °F | 12000BTU/hr |
| Heating at 17 °F | 9700BTU/hr |
| Heating at 5 °F | 8500BTU/hr |
All 25 specifications
| Configuration | |
|---|---|
| Product Type | HP - Mini or Multi Split |
| Compressor Staging | Continuously variable |
| Cold Climate Certified | Yes |
| Connected Capability | No |
| Series | Charmo |
| Indoor-Unit Combinations Rated | 1 |
| Refrigerant | |
| Type | R-410A |
| GWP Rating | R-410A (GWP:2088) |
| Identifiers | |
| Model Number | CHW12KCH18S2-O |
| ENERGY STAR ID | ES_1128541_CHW12KCH18S2-O_06092026023001_29214610239 |
| Partner | 4435273 Canada Inc |
| Date Certified | 2026-06-25 |
| Available From | 2026-06-09 |
| Markets | United States, Canada |
Documentation
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