Axen KS-40W/EN7BP vs SolaX ALT04-SF0
SCOP (35 °C): Axen KS-40W/EN7BP 5.21, SolaX ALT04-SF0 5.25. The SolaX ALT04-SF0 is better on 7 of 13 comparable points.
Who wins where
- Axen KS-40W/EN7BP
- SolaX ALT04-SF0
Biggest differences
| Fact | KS-40W/EN7BP | ALT04-SF0 |
|---|---|---|
| COP A7/W35 | 6.47 | 5.3 |
| Refrigerant charge | 0.61 kg | 0.74 kg |
| Heating capacity (A7/W35) | 4 kW | 4.6 kW |
| Outdoor unit sound power | 53 dB(A) | 48 dB(A) |
| COP A-7/W35 | 3.57 | 3.47 |
| Seasonal efficiency ηs 55 °C | 151 % | 155 % |
Score per area = position (0–100) relative to all 1350 models in this category; higher is better.
| Technical specifications | AxenKS-40W/EN7BP | SolaXALT04-SF0 |
|---|---|---|
| General | ||
| Type (source) | Air-to-water 1 | Air-to-water 1 |
| Performance | ||
| Heating capacity (A7/W35) | 4 kW 2 | 4.6 kW ✓ 3 |
| Rated output 35 °C | 4.2 kW 1 | 4.21 kW ✓ 1 |
| Rated output 55 °C | 4.4 kW ✓ 1 | 4.29 kW 1 |
| Min. outdoor temperature | – | -22 °C 3 |
| Efficiency | ||
| SCOP (35 °C) | 5.21 1 | 5.25 ✓ 1 |
| SCOP (55 °C) | 3.85 1 | 3.95 ✓ 1 |
| Seasonal efficiency ηs 35 °C | 205 % 1 | 207 % ✓ 1 |
| Seasonal efficiency ηs 55 °C | 151 % 1 | 155 % ✓ 1 |
| Energy label 35 °C | A, , , 2 | A, , , 3 |
| Energy label 55 °C | A, , , 2 | A, , , 3 |
| COP A7/W35 | 6.47 ✓ 1 | 5.3 1 |
| COP A2/W35 | 5.19 1 | – |
| COP A-7/W35 | 3.57 ✓ 1 | 3.47 1 |
| Noise | ||
| Outdoor unit sound power | 53 dB(A) 1 | 48 dB(A) ✓ 1 |
| Refrigerant | ||
| Refrigerant | R290 1 | R290 1 |
| Refrigerant GWP | 3 2 | 3 3 |
| Refrigerant charge | 0.61 kg ✓ 1 | 0.74 kg 1 |
| Electrical | ||
| Max. power input | 4.9 kW 1 | 2 kW 1 |
| Connectivity & smart | ||
| SG Ready | Yes 1 | Yes 1 |
Sources
- List of eligible heat pumps (BEG) — Bundesamt für Wirtschaft und Ausfuhrkontrolle (BAFA) · accessed 27 Sept 2026
- Heat Pump Keymark certificates — EHPA / DIN CERTCO (Heat Pump KEYMARK) · accessed 29 Sept 2026
- Heat Pump Keymark certificates — EHPA / DIN CERTCO (Heat Pump KEYMARK) · accessed 29 Sept 2026