Our verdict
Pick the DELLA Vario 12,000 BTU 230V if lower running costs matter most. Pick the DELLA Serena 12,000 BTU 230V if it's going in a bedroom.
The central trade-off
Efficiency. The DELLA Vario 12,000 BTU 230V is rated 23 SEER2 against 22 for the DELLA Serena 12,000 BTU 230V, roughly 4% less cooling energy at the same output.
Noise. The DELLA Serena 12,000 BTU 230V lists 22 dB indoors at its quietest, against 52 dB.
Side by side
| Specification | DELLA Vario 12,000 BTU 230V | DELLA Serena 12,000 BTU 230V |
|---|---|---|
| Cooling (maker) | 12000 BTU | 12000 BTU |
| Heating (maker) | 12000 BTU | 12300 BTU |
| SEER2 | 23 | 22 |
| HSPF2 | Not stated by the maker | Not stated by the maker |
| Heats down to (maker) | Not stated by the maker | Not stated by the maker |
| Voltage | 230 V | 230 V |
| Refrigerant | R-454B | Not stated by the maker |
| Room size (maker) | 550 | 550 sq ft |
| Indoor noise (maker) | 52 db | 22 db |
| Line set included | Not stated by the maker | Not stated by the maker |
| Warranty | Not stated by the maker | Not stated by the maker |
Values are the makers' published specifications. "Not stated" means the maker doesn't publish it.